Artículos de revistas: "Spiro compound"

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DANSHPAJUH, Marjan y Neda HASANZADEH. "Study of influence of anomeric effect on conformational preferences using hybrid density functional theory (DFT) and natural bond orbital (NBO) interpretation". Revue Roumaine de Chimie 68, n.º 1-2 (17 de enero de 2023): 61–74. http://dx.doi.org/10.33224/rrch.2023.68.1-2.06.

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For the relationship between thermodynamic parameters, global hardness, global electronegativity, anomeric effect, structural parameters, and structural properties of dodecahedro-spiro [isochromene-3,2'-pyran] (A), dodecahedro-spiro [isothiocromene-3,2'- thiopyran) (B), dodecahedro-spiro [isochroman-3,2'-thiopyran] (C) and dodecahedro-spiro [isothiochrome-3,2'-pyran] (D) computational methods (B3LYP / 6-311 ++ G **) were used. Results show that the calculated Gibbs free energy and enthalpy differences between the axial- and equatorial- stereoisomers [i.e. ΔG = Geq – Gax, ΔH = Heq- Hax] decrease from compound A to compound B and from compound C to compound D. NBO results show that the anomeric effect associated with the electron delocalization is in benefit of the axial-stereoisomers and with the decrease of the anomeric effect, the values of global hardness (η), and global electronegativity (χ), from compound A to compound B and from compound C to Composition D is also decrease. The correlations between the global hardness, global electronegativity, anomeric effect, structural parameters, and thermodynamic parameters [ΔH, ΔG, and ΔS] of compounds A-D have been investigated. Also, it can be concluded that the stability energy obtained from the numerical values of the anomeric effect and the values calculated theoretically (B3LYP / 6-311 ++ G **) confirmed each other.

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Tripathi, Rahul R. y Ratnamala P. Sonawane. "An Extraction of the Isatin from the Couroupita guianesis (Cannon Ball Tree) and a Novel Synthesis of the N,N'-(2-oxo-3'H-spiro[indoline-3,2'-[1,3,4]thiadiazole]-3',5'-diyl]diacetamidefrom the Isatin". International Letters of Chemistry, Physics and Astronomy 15 (septiembre de 2013): 119–25. http://dx.doi.org/10.18052/www.scipress.com/ilcpa.15.119.

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Isatins are synthetically versatile substrates, where they can be used for the synthesis of a large variety of Isatins and heterocyclic compounds. In this, the isatin were extracted from the floral material of Couroupita guianesis commonly known as an Cannon ball tree. After that, a novel heterocyclic spiro derivative having an IUPAC name N,N’-(2-oxo-3’H-spiro[indoline-3,2’-[1,3,4] thiadiazole]-3’5’-diyl)diacetamide were synthesized , which may be used as raw material for drug synthesis. A spiro compound N,N’-(2-oxo-3’H-spiro[indoline-3,2’-[1,3,4] thiadiazole]-3’5’-diyl)diacetamide were synthesise by refluxing Isatin and thiosemicarbazone in ethanol and then on heating with acetic anhydride underwent to cyclization into intermediate that on acetylation of the NH and NH2 groups afforded the spiro compound.

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Tripathi, Rahul R. y Ratnamala P. Sonawane. "An Extraction of the Isatin from the <i>Couroupita guianesis</i> (Cannon Ball Tree) and a Novel Synthesis of the N,N'-(2-oxo-3'H-spiro[indoline-3,2'-[1,3,4]thiadiazole]-3',5'-diyl]diacetamidefrom the Isatin". International Letters of Chemistry, Physics and Astronomy 15 (29 de junio de 2013): 119–25. http://dx.doi.org/10.56431/p-h7k957.

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Isatins are synthetically versatile substrates, where they can be used for the synthesis of a large variety of Isatins and heterocyclic compounds. In this, the isatin were extracted from the floral material of Couroupita guianesis commonly known as an Cannon ball tree. After that, a novel heterocyclic spiro derivative having an IUPAC name N,N’-(2-oxo-3’H-spiro[indoline-3,2’-[1,3,4] thiadiazole]-3’5’-diyl)diacetamide were synthesized , which may be used as raw material for drug synthesis. A spiro compound N,N’-(2-oxo-3’H-spiro[indoline-3,2’-[1,3,4] thiadiazole]-3’5’-diyl)diacetamide were synthesise by refluxing Isatin and thiosemicarbazone in ethanol and then on heating with acetic anhydride underwent to cyclization into intermediate that on acetylation of the NH and NH2 groups afforded the spiro compound.

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4

Hafez, Hend N., Abdel-Rhman B. A. El-Gazzar y Magdi E. A. Zaki. "Simple approach to thieno[3,2-d]pyrimidines as new scaffolds of antimicrobial activities". Acta Pharmaceutica 66, n.º 3 (1 de septiembre de 2016): 331–51. http://dx.doi.org/10.1515/acph-2016-0029.

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Abstract 6ʹ-(4-Chlorophenyl)-spiro[cyclohexane-1,2ʹ-thieno[3,2-d][1,3] oxazin]-4ʹ(1ʹH)-one (1) was synthesized and used as a starting material for the synthesis of a novel series of spiro compounds having biologically active sulfonamide 2a-e and 3ʹ-(4-acetylphenyl)-6ʹ- (4-chlorophenyl)-1ʹH-spiro[cyclohexane-1,2ʹ-thieno[3,2-d] pyrimidine-4ʹ(3ʹH)-one (3). Compound 2a was used as a key intermediate for the synthesis of sulfonyl carbothioamide derivatives 4a-c. Also, compound 3 was used as an intermediate for the synthesis of 3ʹH-spiro[cyclohexane-1,2ʹ-thieno[3,2-d]pyrimidin]-3ʹ-yl] phenyl}-2-imino-4-(substituted phenyl and/or thienyl)-1,2-dihydropyridine- 3-carbonitrile derivatives 5a-e, 3ʹH-spiro[cyclohexane- 1,2ʹ- thieno[3,2-d]pyrimidin]-3ʹ-yl]phenyl}-2-oxo-4-(substituted phenyl and/or thienyl)-1,2-dihydropyridine-3-carbonitrile derivatives 6a-e, and 4-[(2Z)-3-substituted-arylprop-2-enoyl] phenyl-1ʹH-spiro[cyclohexane-1,2ʹ-thieno[3,2-d]pyrimidine derivatives 7a-e. Cyclocondensation of 7a-e with hydrazine hydrate produced 6ʹ-(4-chlorophenyl)-3ʹ-[4-(5-substituted aryl-4,5-dihydro- 1H-pyrazol-3-yl)phenyl]-1ʹH-spiro[cyclohexane-1,2ʹ-thieno- [3,2-d]pyrimidin]-4ʹ(3ʹH)-ones 8a-e but with hydroxylamine hydrochloride afforded the corresponding isoxazoline derivatives 9a-e. Also, cyclocondensation by thiourea afforded 2-thioxo-1,2- dihydropyrimidin-4-yl)-phenyl-spiro-{cyclohexanethieno[3,2-d] pyrimidin}-4-one derivatives 10a-e. The new compounds were investigated for antimicrobial activity. Compounds 2c, 8b,c, 9b and 10b were the most potent ones against both Gram-negative and Gram-positive bacteria. Compound 8c exhibited higher antifungal activity towards the examined fungi with MIC of 1-2 μmol mL-1 compared to ketoconazole (MIC 2-3 μmol mL-1 ).

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5

Macháček, Vladimír, Makky M. M. Hassanien y Vojeslav Štěrba. "Kinetics and mechanism of spiro adduct formation from and smiles rearrangement of N-methyl-N-(2,4,6-trinitrophenyl)aminoacetanilide. Base-catalyzed transformation of N-(2,4,6-trinitrophenylamino)acetanilide into 2-nitroso-4,6-dinitroaniline". Collection of Czechoslovak Chemical Communications 52, n.º 9 (1987): 2225–40. http://dx.doi.org/10.1135/cccc19872225.

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The paper deals with kinetics and mechanism of the reaction of N-(2,4,6-trinitrophenyl)aminoacetanilide (IIa) with methoxide ion and with the reaction kinetics and product structure of the reaction of N-methyl-N-(2,4,6-trinitrophenyl)aminoacetanilide (IIb) in methanolic buffers. The main product of the reaction of compound IIa with methoxide is 2-nitroso-4,6-dinitroaniline along with about 3% spiro adduct. The dependence of the experimental rate constant kexp of the reaction with methoxide on the methoxide concentration is similar to that of the reaction of N-(2,4,6-trinitrophenyl)glycine methylamide, however, compound IIa reacts about 2·5 times faster and produces the spiro adduct in an about four times smaller amount. In basic acetate buffers, compound IIb is transformed quantitatively into the spiro adduct. In chloroacetate buffers, the reverse ring opening of the spiro adduct prevails. The ring opening takes two ways: A specific acid catalyzed one and a non-catalyzed one. Corresponding therewith is the non-catalyzed and specific base catalyzed formation of the spiro adduct. In aniline-anilinium chloride buffers, equilibrium is rapidly established between the spiro adduct and 2-methylamino-N-phenyl-N-(2,4,6-trinitrophenyl)acetamide hydrochloride. The mixture of the two compounds is transformed gradually into compound IIb which shows the highest thermodynamic stability in the given medium. At [H+] > 10-3 mol l-1 the thermodynamically most stable species is 2-methylamino-N-phenyl-N-(2,4,6-trinitrophenyl)acetamide hydrochloride.

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6

Nakano, Koji, Ko Takase y Keiichi Noguchi. "Furan-Containing Chiral Spiro-Fused Polycyclic Aromatic Compounds: Synthesis and Photophysical Properties". Molecules 27, n.º 16 (11 de agosto de 2022): 5103. http://dx.doi.org/10.3390/molecules27165103.

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Spiro-fused polycyclic aromatic compounds (PACs) have received growing interest as rigid chiral scaffolds. However, furan-containing spiro-fused PACs have been quite limited. Here, we design spiro[indeno[1,2-b][1]benzofuran-10,10′-indeno[1,2-b][1]benzothiophene] as a new family of spiro-fused PACs that contain a furan unit. The compound was successfully synthesized in enantiopure form and also transformed to its S,S-dioxide derivative and the pyrrole-containing analog via aromatic metamorphosis. The absorption and emission properties of the obtained furan-containing chiral spiro-fused PACs are apparently different from those of their thiophene analogs that have been reported, owing to the increased electron-richness of furan compared to thiophene. All of the furan-containing chiral spiro-fused PACs were found to be circularly polarized luminescent materials.

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7

Konyar, Dilan, Cenk A. Andac y Erdem Buyukbingol. "Design, Synthesis and Cytotoxic Activity of Spiro(oxindole-3-3'- pyrrolidine) Derivatives". Letters in Drug Design & Discovery 15, n.º 1 (3 de enero de 2018): 37–45. http://dx.doi.org/10.2174/1570180814666170810120634.

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Background: Spiro[pyrrolidine-3,3'-oxindole] compounds are reported to be highly bioactive natural and synthetic products. Initially, spirooxindole alkaloids were isolated from plants of the Apocynaceae and Rubiaceae families, which were found to have a common scaffold, spiro[pyrrolidine-3,3'-oxindole], exhibiting anticancer activities., we specifically aimed at the synthesis, characterization and anticancer activity of novel spiro[pyrrolidine-3,3' -oxindole] derivatives, compounds 6a-c and 7. Methods: The synthesis was initiated by Knovenegal condensation of indole-2-one with an appropriate benzaldehyde in presence of piperidine to afford compounds 3a-c. Compounds 6a-c were synthesized by an asymmetric 1,3-dipolar cycloaddition between compounds 3a-c and (2S, 3R)-2, 3, 5, 6-tetrahydro-2, 3-diphenyl-1, 4-oxazin-6-one, which is an intermediate compound formed by the Schiff base reaction between 3-methyl-butanal and (2S, 3R)-2, 3, 5, 6-tetrahydro-2, 3-diphenyl- 1,4-oxazin-6-one, in presence of molecular sieves (4Å) under argon atmosphere. Compound 6a was then reacted with ethylamine-HCl in THF at room temperature to yield compound 7. Results: Cytotoxic effects of the compounds synthesized were determined on Huh7, MV, HCT116 and MCF7 cancer cell lines by the NCI-60 Sulforhodamine B Assay, using (S)-(+)-Camptothecin as a positive control. In general, target compounds showed better cytotoxic activities against the MCF7 and HCT116 cancer cell lines. It was found that compound 7 exhibited the most potent inhibitory activity with IC50 values of 4.8 µM, 3.9 µM, 14.9 µM and 8.2 µM against the MCF7, HCT116, MV and Huh7 cell lines, respectively. Conclusion: It was determined that compounds 6a&6b possess C6'(S)|C8'(R)|C9'(R) stereochemistry and compound 7 adopts C2'(S)|C4'(R)|C5'(R) stereochemistry. Cytotoxicity studies suggest that compound 7 gave rise to the highest anticancer activity against MCF7, HCT116, and Huh7 cancer cell lines.

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8

Barakat, Assem, Mohammad Shahidul Islam, M. Ali, Abdullah Mohammed Al-Majid, Saeed Alshahrani, Abdullah Saleh Alamary, Sammer Yousuf y M. Iqbal Choudhary. "Regio- and Stereoselective Synthesis of a New Series of Spirooxindole Pyrrolidine Grafted Thiochromene Scaffolds as Potential Anticancer Agents". Symmetry 13, n.º 8 (4 de agosto de 2021): 1426. http://dx.doi.org/10.3390/sym13081426.

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A series of new spiro-heterocycles engrafted spirooxindole/pyrrolidine/thiochromene scaffolds was synthesized by the three-component 1,3-dipolar cycloaddition reactions in a fully controlled regio- and stereo-selective fashion. Condensation of several substituted isatin derivatives with L-proline generated the azomethine ylides which subsequently reacted with chalcones based thiochromene scaffold, and finally afforded the target spiro-compounds. This simple protocol furnished a structurally complex, biologically relevant spiro-heterocycles in good yields through a one-pot process. All synthesized chalcone-based thiochromene, along with the spirooxindole/pyrrolidine/thiochromene scaffolds, were tested for their anticancer activity against four cancer cell lines (PC3, HeLa, MCF-7, and MDA-MB231). Toxicity of these compounds was also evaluated against human fibroblast BJ cell line, and they appeared to be not cytotoxic. For the prostate cancer (PC3) cell line, the most active hybrid, among synthesized series, was compound (7f, IC50 = 8.7 ± 0.7 µM). The most potent spirooxindole/pyrrolidine/thiochromene hybrid against cervical (HeLa) cancer cells was compound (7k, IC50 = 8.4 ± 0.5 µM) having chlorine and p-trifluoromethyl substituents attached to phenyl rings. Finally, against the MCF-7 and MDA-MB231 breast cancer cell lines, compound (7d) was the most active member of this series (IC50 = 7.36 ± 0.37, and 9.44 ± 0.32 µM, respectively).

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9

Westphal, Regina, Eclair Venturini Filho, Laiza Bruzadelle Loureiro, Cláudio Francisco Tormena, Claudia Pessoa, Celina de Jesus Guimarães, Mariana Palmeira Manso et al. "Green Synthesis of Spiro Compounds with Potential Anticancer Activity through Knoevenagel/Michael/Cyclization Multicomponent Domino Reactions Organocatalyzed by Ionic Liquid and Microwave-Assisted". Molecules 27, n.º 22 (19 de noviembre de 2022): 8051. http://dx.doi.org/10.3390/molecules27228051.

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In this work a microwave-assisted Knoevenagel/Michael/cyclization multicomponent domino methodology, using ethanol as solvent and the ionic liquid 1-methylimidazolium chloride as catalyst was developed for the synthesis of spiro compounds. The reaction conditions considered ideal were determined from a methodological study varying solvent, catalyst, amount of catalyst, temperature, and heating mode. Finally, the generality of the methodology was evaluated by exploring the scope of the reaction, varying the starting materials (isatin, malononitrile, and barbituric acid). Overall, the twelve spiro compounds were synthesized in good yields (43–98%) and the X-ray structure of compound 1b was obtained. In addition, the in vitro antiproliferative activities of the spirocycles against four types of human cancer cell lines including HCT116 (human colon carcinoma), PC3 (prostate carcinoma), HL60 (promyelocytic leukemia), and SNB19 (astrocytoma) were screened by MTT-based assay. It is noteworthy that spiro compound 1c inhibited the four cell lines tested with the lowest IC50 values: 52.81 µM for HCT116, 74.40 µM for PC3, 101 µM for SNB19, and 49.72 µM for HL60.

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10

Wu, Mengyao, Yilin Wang, Xiaojun Tan y Jinsong Gu. "Theoretical study on the reaction between phosphacyclopropenylidene and ethylene: An alternative approach to the formation of phosphorus-bearing heterocyclic compound". Journal of the Serbian Chemical Society 85, n.º 9 (2020): 1175–84. http://dx.doi.org/10.2298/jsc191217026w.

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The reaction mechanism between phosphacyclopropenylidene and ethylene has been systematically investigated at the B3LYP/6-311++G(d,p) level of theory in order to better understand the reactivity of unsaturated cyclic phosphorus-bearing carbene. Geometry optimizations and vibrational analyses have been performed for the stationary points on the potential energy surface of the system. Calculations show that the spiro bicyclic intermediate could be produced through the cycloaddition process between phosphacyclopropenylidene and ethylene initially. The reaction mechanism is illustrated with the frontier molecular orbital theory. Introduction of electron-withdrawing group in phosphacyclopropenylidene will better facilitate the addition process. Through subsequent ring-expanding and hydrogen-migrating process, fuse-ring and allene compounds could be produced, respectively. Furthermore, it?s easy for spiro bicyclic intermediate and another ethylene to form a spiro tricyclic compound. This study is helps to understand the reactivity of phosphacyclopropenylidene, the evolution of phosphorus-bearing molecules in space, and to offer an alternative approach to the formation of phosphorus-bearing heterocyclic compound.

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Wang, Yilin, Mengyao Wu, Xiaojun Tan y Jinsong Gu. "Insights into the reaction mechanism between phosphacyclopropenylidene and methyleneimine: A theoretical study". Main Group Chemistry 19, n.º 3 (14 de octubre de 2020): 237–44. http://dx.doi.org/10.3233/mgc-200906.

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The reaction mechanism between phosphacyclopropenylidene and methyleneimine has been systematically investigated at the M06–2X/6–311++G(d,p) level of theory in order to better understand the reactivity of unsaturated cyclic phosphorus-bearing carbene. Geometry optimizations and vibrational analyses have been conducted for the stationary points on the potential energy surface of the system. Calculations show that the spiro bicyclic intermediate could be produced through the cycloaddition process between phosphacyclopropenylidene and methyleneimine initially. The reaction mechanism is illustrated with frontier molecular orbital theory. Introduction of electron-withdrawing group in phosphacyclopropenylidene will better facilitate the addition process. Through subsequent ring-expanding and hydrogen-migrating process, fuse-ring and allene compounds could be produced, respectively. Furthermore, it’s easy for spiro bicyclic intermediate and another methyleneimine to form a spiro tricyclic compound. This study is helpful to understand the reactivity of phosphacyclopropenylidene, the evolution of phosphorus-bearing molecules in space, and to offer an alternative approach to the formation of phosphorus-bearing heterocyclic compound.

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12

Shukla, Paritosh, Ashok Sharma, Leena Fageria y Rajdeep Chowdhury. "Novel Spiro/non-Spiro Pyranopyrazoles: Eco-Friendly Synthesis, In-vitro Anticancer Activity, DNA Binding, and In-silico Docking Studies". Current Bioactive Compounds 15, n.º 2 (12 de marzo de 2019): 257–67. http://dx.doi.org/10.2174/1573407213666170828165512.

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Background: Cancer being a deadly disease, many reports of new chemical entities are available. Pyranopyrazole (PPZ) compounds have also been disclosed as bioactive molecules but mainly as antimicrobial agents. Based on one previous report and our interest in anticancer drug design, we decided to explore PPZs as anticancer agents. To the best of our knowledge, we found that a comprehensive study, involving synthesis, in-vitro biological activity determination, exploration of the mechanism of inhibition and finally in-silico docking studies, was missing in earlier reports. This is what the present study intends to accomplish. Methods: Ten spiro and eleven non-spiro PPZ molecules were synthesized by environment-friendly multicomponent reaction (MCR) strategy. After subjecting each of the newly synthesized molecules to Hep3b hepatocellular carcinoma cell lines assay, we selectively measured the Optical Density (OD) of the most active ones. Then, the compound exhibiting the best activity was docked against human CHK- 1 protein to get an insight into the binding affinities and a quick structure activity relationship (SAR) of the PPZs. Results: The two series of spiro and non-spiro PPZs were easily synthesized in high yields using microwave assisted synthesis and other methods. Among the synthesized compounds, most compounds showed moderate to good anticancer activity against the MTT assay. After performing the absorbance studies we found that the non-spiro molecules showed better apoptosis results and appeared to bind to DNA causing disruption in their structures. Finally, the docking results of compound 5h (having N,Ndimethylamino substituted moiety) clearly showed good binding affinities as predicted by our experimental findings. Conclusion: The paper describes a comprehensive synthesis, in-vitro and docking studies done on new PPZs. The newly synthesized series of spiro and non-spiro PPZs were found to possess antineoplasmic activity as evinced by the studies on hep3b cells. Also, the UV visible absorbance study gave clues to the possible binding of these molecules to the DNA. Docking studies corroborated well with the experimental results. Thus, these new molecules appear to be potential anticancer agents, but further studies are required to substantiate and elaborate on these findings.

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13

Rys, Paul, Ruth Weber y Qinglan Wu. "Light-induced change of the molecular charge in a spironaphthoxazine compound". Canadian Journal of Chemistry 71, n.º 11 (1 de noviembre de 1993): 1828–33. http://dx.doi.org/10.1139/v93-228.

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To evaluate the experimental conditions for the light-induced change of the molecular charge, the dependence of the photochromic reaction behaviour of the indolino spiro naphthoxazine compound 1,3,3-trimethyl-spiro[2H-indol 2,3′-[3H]naphth[2,1-b]-[1,4]oxazine] on the pH value of the solution is investigated. In the absence of UV light an acid–base equilibrium between the spiro form and a protonated closed form is established. By irradiation under appropriate acidic conditions the spiro form can be transformed into an open cationic form through the merocyanine form. Between the two open forms an acid–base equilibrium is established. Except for the closed protonated form the structures are confirmed by mean of NMR. The kinetics of the thermal ring-closing reaction of both forms are investigated by flash photolysis. It is shown that the ring-closing reaction proceeds exclusively via the merocyanine form. The pK values determined for both equilibria give the pH range, in which the light-induced change of the molecular charge occurs.

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14

Kim, Seung Hyun, Sang Hyun Sung, Soo Young Choi, Young Keun Chung, Jinwoong Kim y Young Choong Kim. "Idesolide: A New Spiro Compound fromIdesiapolycarpa". Organic Letters 7, n.º 15 (julio de 2005): 3275–77. http://dx.doi.org/10.1021/ol051105f.

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15

Tada, Masahiro, Masashi Nagai, Chieko Okumura, Yasuko Osano y Takao Matsuzaki. "Novel Spiro-Compound, Hyperolactone fromHypericum chinenseL." Chemistry Letters 18, n.º 4 (abril de 1989): 683–86. http://dx.doi.org/10.1246/cl.1989.683.

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Flefel, Eman M., Walaa I. El-Sofany, Reem A. K. Al-Harbi y Mahmoud El-Shahat. "Development of a Novel Series of Anticancer and Antidiabetic: Spirothiazolidines Analogs". Molecules 24, n.º 13 (9 de julio de 2019): 2511. http://dx.doi.org/10.3390/molecules24132511.

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4-(4-Aminophenyl)-1-thia-4-azaspiro[4.5]decan-3-one 1 was prepared and allowed to react with nitrogen nucleophiles to give the corresponding hydrazones 2–4. Further, compound 1 underwent diazotization and afforded the parallel hydrazono derivative 5; moreover, compound 1 refluxed with active methylene derivatives yielded the corresponding aminospirothiazolo pyridine–carbonitrile derivative 6 and spirothiazolopyridinone–carbonitrile derivative 7. Condensation of spirothiazolidine 1 with 4-chlorobenzaldehyde gave the corresponding spiro arylidiene derivative 8, which was utilized as a component of Micheal addition to react with excess of nitrogen nucleophiles to yield novel ring frameworks 4-(3′-(4-chlorophenyl)–spiro [cyclohexane-1,5′-pyrazolo[3,4-d]thiazol]-6′(1′H)-yl)aniline (9) and 4-(3′-(4-chlorophenyl)-6′H- spiro[cyclohexane-1,5′-thiazolo[5,4-d]isoxazol]-6′-yl)aniline (10). Finally, when spirothiazolo pyridinone–carbonitrile derivative 7 sodium salt generated in situ was reacted with different alkyl halides, it produced the corresponding N-derivatives 12–16. Three compounds, 6, 14, and 16, showed high significantly anticancer activities compared with Doxorubicin® (positive control) against human breast carcinoma (MCF-7) and human liver carcinoma (HepG-2) cell lines. On the other hand, compounds 6 and 9 showed higher therapeutic indices for both of alpha-amylase inhibitor and alpha-glucosidase inhibitor than the other tested compounds compared with the antidiabetic Acarbose (positive control).

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Sepsey Für, Csilla y Hedvig Bölcskei. "New Spiro[cycloalkane-pyridazinone] Derivatives with Favorable Fsp3 Character". Chemistry 2, n.º 4 (6 de octubre de 2020): 837–48. http://dx.doi.org/10.3390/chemistry2040055.

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The large originator pharmaceutical companies need more and more new compounds for their molecule banks, because high throughput screening (HTS) is still a widely used method to find new hits in the course of the lead discovery. In the design and synthesis of a new compound library, important points are in focus nowadays: Lipinski’s rule of five (RO5); the high Fsp3 character; the use of bioisosteric heterocycles instead of aromatic rings. With said aim in mind, we have synthesized a small compound library of new spiro[cycloalkane-pyridazinones] with 36 members. The compounds with this new scaffold may be useful in various drug discovery projects.

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Song, Fuhang, Rui Lin, Na Yang, Jia Jia, Shangzhu Wei, Jiahui Han, Jiangpeng Li, Hongkai Bi y Xiuli Xu. "Antibacterial Secondary Metabolites from Marine-Derived Fungus Aspergillus sp. IMCASMF180035". Antibiotics 10, n.º 4 (3 de abril de 2021): 377. http://dx.doi.org/10.3390/antibiotics10040377.

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Four new secondary metabolites, including one spiro[anthracenone-xanthene] derivative aspergiloxathene A (1), one penicillide analogue, Δ2′-1′-dehydropenicillide (2), and two new phthalide derivatives, 5-methyl-3-methoxyepicoccone (3) and 7-carboxy-4-hydroxy-6-methoxy-5-methylphthalide (4), together with four known compounds, yicathin C (5), dehydropenicillide (6), 3-methoxyepicoccone (7), 4-hydroxy-6-methoxy-5-methylphthalide (8), were identified from the marine-derived fungus Aspergillus sp. IMCASMF180035. Their structures were determined by spectroscopic data, including high-resolution electrospray ionization mass spectrometry (HRESIMS), 1D and 2D nuclear magnetic resonance (NMR) techniques. Compound 1 was identified as the first jointed molecule by xanthene and anthracenone moieties possessing an unprecedented carbon skeleton with spiro-ring system. All compounds were evaluated activities against Staphylococcus aureus, methicillin resistant S. aureus (MRSA), Escherichia coli, Escherichia faecium, Pseudomonas aeruginosa, and Helicobacter pylori. Compound 1 showed significant inhibitory effects against S. aureus and MRSA, with minimum inhibitory concentration (MIC) values of 5.60 and 22.40 µM. Compounds 2 and 6 exhibited potent antibacterial activities against H. pylori, with MIC values of 21.73 and 21.61 µM, respectively.

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19

Mohamed, Magda F., Amr Mohamed Abdelmoniem, Ahmed H. M. Elwahy y Ismail A. Abdelhamid. "DNA Fragmentation, Cell Cycle Arrest, and Docking Study of Novel Bis Spiro-cyclic 2-oxindole of Pyrimido[4,5-b]quinoline-4,6-dione Derivatives Against Breast Carcinoma". Current Cancer Drug Targets 18, n.º 4 (6 de abril de 2018): 372–81. http://dx.doi.org/10.2174/1568009617666170630143311.

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Background: Recently, it is reported that heterocycles containing pyrimidoquinoline moiety show a broad spectrum of medicinal and pharmacological properties including anticancer, anti-microbial, anti-inflammatory activities, analgesic and antiviral. In additions, spirocyclicoxindole containing compounds represent an important class of compounds that exhibit wide range of biological properties. The asymmetric chiral spiro carbon is considered to be the main criteria of the bioactivities. Spirooxindole structures represent the main skeleton for various alkaloids and pharmaceutically important compounds. Among them, the naturally occurring pyrrolidinylespirooxindole alkaloid, horsifiline that exhibits anticancer activity against human brain cancer cell lines. Objective: The objective of this study is the synthesis of novel bis spiro-cyclic 2-oxindole of pyrimido[4,5-b]quinoline derivatives and evaluate the anticancer activity of new compounds for synergistic purpose. Different genetic tools were used in an attempt to know the mechanism of action of this compound against breast cancer. Method: An efficient one pot synthesis of bis spiro-cyclic 2-oxindole derivatives of pyrimido[4,5- b]quinoline-4,6-dione using 6-aminouracil, bis-isatin and dimedone has been developed. The cytotoxic effect against different human cell lines MCF7, HCT116 and A549 cell lines was evaluated. The derivative 6a, was found the most encouraging compound in this series and it was selected for molecular studies against MCF7. Results: Our data indicated that compound 6a is an attractive target for breast cancer, as it inhibits proliferation, cell cycle progression and induces apoptosis of tumor cells. This inhibition is mediated by fragmentation of genomic DNA, up-regulation of [caspase-3, tumor suppressor gene p53, and pro-apoptotic gene BAX], and down-regulation of anti-apoptotic BCL2 gene. In additions it caused cell cycle arrest in S phase. This work provides an evidence of the potent effect of the new compound 6a and assists in the progress of new healing agents for cancer. Conclusion: We have developed an efficient method for the synthesis of novel bioactive bis spirocyclic 2-oxindole derivatives incorporating pyrimido[4,5-b]quinoline derivatives. Most of our new derivatives give potent cytotoxic effect more than the standard drug Fluorouracil (5-FU) especially, compound 6a which was the most active and promising one in this series against MCF7, HCT116, and A549 cell lines.

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20

Bernet, Bruno, Paul M. Bishop, Maurice Caron, Takeshi Kawamata, Bernard L. Roy, Luc Ruest, Gilles Sauvé, Pierre Soucy y Pierre Deslongchamps. "Formal total synthesis of erythromycin A. Part II. Preparation of a 1,7-dioxaspiro[5.5]undecane derivative of erythronolide A seco acid methyl ester from erythromycin A". Canadian Journal of Chemistry 63, n.º 10 (1 de octubre de 1985): 2814–18. http://dx.doi.org/10.1139/v85-469.

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21

Kotha, Sambasivarao, Mohammad Saifuddin, Rashid Ali y Gaddamedi Sreevani. "Spiro annulation of cage polycycles via Grignard reaction and ring-closing metathesis as key steps". Beilstein Journal of Organic Chemistry 11 (5 de agosto de 2015): 1367–72. http://dx.doi.org/10.3762/bjoc.11.147.

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A simple synthetic strategy to C 2-symmetric bis-spiro-pyrano cage compound 7 involving ring-closing metathesis is reported. The hexacyclic dione 10 was prepared from simple and readily available starting materials such as 1,4-naphthoquinone and cyclopentadiene. The synthesis of an unprecedented octacyclic cage compound through intramolecular Diels–Alder (DA) reaction as a key step is described. The structures of three new cage compounds 7, 12 and 18 were confirmed by single crystal X-ray diffraction studies.

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22

Macháček, Vladimír, Makky M. M. Hassanien, Vojeslav Štěrba y Antonín Lyčka. "Formation of the Meisenheimer spiro adduct of N-(2,4,6-trinitrophenyl)alanine methylamide and its rearrangement to 2-amino-N-methyl-N-(2,4,6-trinitrophenyl)propanamide". Collection of Czechoslovak Chemical Communications 51, n.º 9 (1986): 1972–85. http://dx.doi.org/10.1135/cccc19861972.

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N-(2,4,6-trinitrophenyl)alanine methylamide (I) undergoes base-catalyzed cyclization in methanol to give the spiro adduct II. In aniline-anilinium chloride buffers, the spiro adduct is protonated at the oxygen atom of 2-nitro group to give the neutral compound III. In 4-bromoaniline buffers or by action of methanolic hydrogen chloride, the compound III is opened to E and Z isomers of 2-amino-N-methyl-N-(2,4,6-trinitrophenyl)propanamide hydrochloride (IV). The rate-limiting step of cyclization of compound Z-IV to compound III consists in the isomerization Z-IV → E-IV. At higher pH values (acetate buffers), the rate-limiting step is gradually changed to the isomerization of 2-amino-N-methyl-N-(2,4,6-trinitrophenyl)propanamide (Z-V → E-V).

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23

Sayed, Hayam, Hebat-Allah Abbas, Eman Morsi, Abd Amr y Nayera Abdelwahad. "Antimicrobial activity of some synthesized glucopyranosyl-pyrimidine carbonitrile and fused pyrimidine systems". Acta Pharmaceutica 60, n.º 4 (1 de diciembre de 2010): 479–91. http://dx.doi.org/10.2478/v10007-010-0033-8.

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Antimicrobial activity of some synthesized glucopyranosyl-pyrimidine carbonitrile and fused pyrimidine systems 3-Amino-5-(4-chlorophenylamino)-4-cyanofuran-2-carboxamide (2) was used as the key molecule for preparation of various furopyrimidines 3-9 and formation of spiro-cycloalkane furopyrimidines 10, 11. Also, poly fused heterocyclic compounds 13-17 were prepared from compound 2. The synthesized compounds were screened for their antimicrobial activity.

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24

Maihesuti, L., P. Lan, M. Imerhasan, K. A. Eshbakova y X. Jia. "A New Spiro Compound from Caragana acanthophylla". Chemistry of Natural Compounds 53, n.º 4 (julio de 2017): 646–48. http://dx.doi.org/10.1007/s10600-017-2081-5.

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25

Silva, Daiana K. Frade, Sâmia S. Duarte, Thaís M. H. Lisboa, Rafael C. Ferreira, Ana Luíza de O. Lopes, Deyse C. M. Carvalho, Sandra Rodrigues-Mascarenhas et al. "Antitumor Effect of a Novel Spiro-Acridine Compound is Associated with Up-Regulation of Th1-Type Responses and Antiangiogenic Action". Molecules 25, n.º 1 (20 de diciembre de 2019): 29. http://dx.doi.org/10.3390/molecules25010029.

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Tumor cells have specific features, including angiogenesis induction, cell cycle dysregulation, and immune destruction evasion. By inducing a T helper type 2 (Th2) immune response, tumor cells may favor immune tolerance within the tumor, which allows progression of cancer growth. Drugs with potential antitumor activity are the spiro-acridines, which is a promising new class of acridine compounds. Herein, the novel spiro-acridine (E)-5′-oxo-1′-((3,4,5-trimethoxybenzylidene)amino)-1′,5′-dihydro-10H-spiro[acridine-9,2′-pyrrole]-4′-carbonitrile (AMTAC-17) was synthesized and tested for antitumor effects. Toxicity evaluation was performed in mice after acute treatment (2000 mg/kg, intraperitoneally, i.p.). The Ehrlich ascites carcinoma model was used to investigate the antitumor activity of AMTAC-17 (12.5, 25, or 50 mg/kg, i.p.) after seven days of treatment. Effects on the cell cycle, angiogenesis, and inflammatory responses were investigated. LD50 (lethal dose 50%) was estimated to be higher than 5000 mg/kg. AMTAC-17 reduced the Ehrlich tumor’s total viable cancer cells count and peritumoral micro-vessels density, and induced an increase in the sub-G1 peak. Additionally, there was an increase of Th1 cytokine profile levels (IL-1β, TNF-α, and IL-12). In conclusion, the spiro-acridine compound AMTAC-17 presents low toxicity, and its in vivo antitumor effect involves modulation of the immune system to a cytotoxic Th1 profile and a reduction of tumor angiogenesis.

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26

El-Ossaily, Y. A. B., R. M. Zaki y S. A. Metwally. "Investigation and Synthesis of Some Novel Spiro Heterocycles Related to Indoline Moiety". Journal of Scientific Research 6, n.º 2 (22 de abril de 2014): 293–307. http://dx.doi.org/10.3329/jsr.v6i2.17590.

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Reactions of indole-2,3-dione 1 with 2-mercaptobenzimidazole, o-phenylenediamine, 2-aminophenol, 2-aminobenzothiazole, 2-aminobenzimidazole and 3-methyl-1-phenyl-2-pyrazolin-5-one were carried out to give compounds spiroindolethiazetobenzimidazole 2, spirobenzimidazole(oxazole)indoline 3a,b, benzothiazol(imidazol) iminoindolinone 4a,b and methyloxoindolylidenepyrazolone 5 respectively. Compound 5 was reacted with 2-aminophenol as well as o-phenylenediamine to give new spirooxazepine and diazepine derivatives 6a,b respectively. Reaction of 5 with nitrogen nucleophiles as well as carbon nucleophiles was investigated to furnish new spiro heterocycles 7-11. The reaction of 2-(2-oxo-1,2-dihydroindol-3-ylidene)malononitrile compound 12 with 3-methyl-1-phenyl-2-pyrazoline-5-one was carried out to give spiroindolopyranopyrazolo derivative 13. Compounds 4a,b was reacted with thioglycolic acid to give thiazolidinone derivatives 14a,b. Epoxidation of 5 using monoperoxyphthalic acid magnesium salt hexahydrate and hydrogen peroxide were executed to afford the novel dispiro (2-pyrazolin oxiraneindoline)dione compound 15. The chemical structures of the synthesized compounds were well established by elemental and spectral analyses. Keywords: Spiroheterocycles; Epoxidation; Diazapines, Oxazepines; Spirothiazolidinone. © 2014 JSR Publications. ISSN: 2070-0237 (Print); 2070-0245 (Online). All rights reserved. doi: http://dx.doi.org/10.3329/jsr.v6i2.17590 J. Sci. Res. 6 (2), 303-317 (2014)

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27

Wang, Guisheng, Yilin Yuan, Zhaokun Li, Junhao Zhu, Zhigang She y Yan Chen. "Cytosporones with Anti-Inflammatory Activities from the Mangrove Endophytic Fungus Phomopsis sp. QYM-13". Marine Drugs 21, n.º 12 (7 de diciembre de 2023): 631. http://dx.doi.org/10.3390/md21120631.

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Six previously undescribed cytosporone derivatives (phomotones A-E (1–5) and phomotone F (13)), two new spiro-alkanol phombistenes A-B (14–15), and seven known analogs (6–12) were isolated from the mangrove endophytic fungus Phomopsis sp. QYM-13. The structures of these compounds were elucidated using spectroscopic data analysis, electronic circular dichroism (ECD), and 13C NMR calculations. Compound 14 features an unprecedented 1,6-dioxaspiro[4.5]decane ring system. All isolates were evaluated for their inhibitory effect on nitric oxide (NO) in LPS-induced RAW264.7 cells. The results showed that compounds 1, 6, 8, and 11 exhibited potent bioactivities by comparing with positive control. Then, compound 1 displayed the anti-inflammatory effect by inhibiting the MAPK/NF-κB signaling pathways. Molecular docking further revealed the possible mechanism of compound 1 interaction with ERK protein.

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28

Tourneur, P., F. Lucas, C. Quinton, Y. Olivier, R. Lazzaroni, P. Viville, J. Cornil y C. Poriel. "White-light electroluminescence from a layer incorporating a single fully-organic spiro compound with phosphine oxide substituents". Journal of Materials Chemistry C 8, n.º 41 (2020): 14462–68. http://dx.doi.org/10.1039/d0tc03285a.

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29

Govindan, E., PanneerSelvam Yuvaraj, Boreddy Siva Rami Reddy, K. Premalatha y A. SubbiahPandi. "(4S)-5′-Chloro-3,7,7-trimethyl-5,6,7,8-tetrahydro-4H-spiro[1,2-oxazolo[5,4-b]quinoline-4,3′-indole]-2′,5-dione". Acta Crystallographica Section E Structure Reports Online 70, n.º 2 (18 de enero de 2014): o173. http://dx.doi.org/10.1107/s1600536814000191.

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In the title compound, C20H18ClN3O3, the five- and six-membered heterocycles fused through a spiro C atom are inclined to each other at an angle of 87.4 (1)°. In the tricyclic ring system, the cyclohexene ring adopts an envelope conformation with the spiro atom as the flap. In the crystal, two sets of N—H...O hydrogen bonds link the molecules into columns containing centrosymmetricR22(7) ring motifs and propagating along theb-axis direction.

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30

Mohamed, Abou-El-Hamd H., Ali K. Khalafallah y Afifi H. Yousof. "Biotransformation of Glabratephrin, a Rare Type of Isoprenylated Flavonoids, by Aspergillus niger". Zeitschrift für Naturforschung C 63, n.º 7-8 (1 de agosto de 2008): 561–64. http://dx.doi.org/10.1515/znc-2008-7-816.

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Microbial transformation of glabratephrin, the major isolated compound from Tephrosia purpurea, afforded pseudosemiglabrin. The formation of the transformed compound seems to be performed via ring opening-closure of a five-membered ring causing transformation from a spiro into a fused system. The structure of the transformed compound was determined by comprehensive NMR studies, including DEPT, COSY, HMQC, NOE and MS.

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31

Schaefer, W. P. y J. Abulū. "An Indanyl Precursor to a Chiral Spiro Compound". Acta Crystallographica Section C Crystal Structure Communications 51, n.º 11 (15 de noviembre de 1995): 2364–66. http://dx.doi.org/10.1107/s0108270195005609.

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32

Schaefer, W. P., L. M. Henling, H. C. McBay y J. Abulū. "A Pinacol Precursor to a Chiral Spiro Compound". Acta Crystallographica Section C Crystal Structure Communications 52, n.º 1 (15 de enero de 1996): 104–7. http://dx.doi.org/10.1107/s0108270195010213.

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33

Augustine, T., V. Ramkumar, S. Arul Antony y Charles C. Kanakam. "6′′-Methoxy-1′-methyl-4′-phenylacenaphthene-1-spiro-2′-pyrrolidine-3′-spiro-3′′-chroman-2,4′′-dione". Acta Crystallographica Section E Structure Reports Online 63, n.º 11 (26 de octubre de 2007): o4412. http://dx.doi.org/10.1107/s1600536807051264.

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34

Kuznetsova, Juliana V., Varvara T. Tkachenko, Lada M. Petrovskaya, Maria E. Filkina, Dmitry E. Shybanov, Yuri K. Grishin, Vitaly A. Roznyatovsky et al. "[3+2]-Cycloaddition of Nitrile Imines to Parabanic Acid Derivatives—An Approach to Novel Spiroimidazolidinediones". International Journal of Molecular Sciences 25, n.º 1 (19 de diciembre de 2023): 18. http://dx.doi.org/10.3390/ijms25010018.

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Approximately 1,3-Dipolar cycloaddition of imidazolidine derivatives containing exocyclic double bonds is a convenient method of creating spiro-conjugated molecules with promising anticancer activity. In this work, the derivatives of parabanic acid (2-thioxoimidazolidine-4,5-diones and 5-aryliminoimidazolidine-2,4-diones) were first investigated as dipolarophiles in the reactions with nitrile imines. The generation of nitrile imines was carried out either by the addition of tertiary amine to hydrazonoyl chlorides «drop by drop» or using the recently proposed diffusion mixing technique, which led to ~5–15% increases in target compound yields. It was found that the addition of nitrile imines to C=S or C=N exocyclic double bonds led to 1,2,4-thiazolines or triazolines and occurred regioselectively in accordance with the ratio of FMO coefficients of reactants. The yield of the resulting spiro-compound depended on the presence of alkyl substituents in the nitrile imine structure and was significantly decreased in reactions with imines with strong electron donor or electron-withdrawing groups. Some of the obtained compounds showed reasonable in vitro cytotoxicity. IC50 values were calculated for HCT116 (colon cancer) cells using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) test.

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35

Guan, Zong, Jan C. Namyslo, Martin H. H. Drafz, Martin Nieger y Andreas Schmidt. "Dimerisation, rhodium complex formation and rearrangements of N-heterocyclic carbenes of indazoles". Beilstein Journal of Organic Chemistry 10 (10 de abril de 2014): 832–40. http://dx.doi.org/10.3762/bjoc.10.79.

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Deprotonation of indazolium salts at low temperatures gives N-heterocyclic carbenes of indazoles (indazol-3-ylidenes) which can be trapped as rhodium complexes (X-ray analysis). In the absence of Rh, the indazol-3-ylidenes spontaneously dimerize under ring cleavage of one of the N,N-bonds and ring closure to an indazole–indole spiro compound which possesses an exocyclic imine group. The E/Z isomers of the imines can be separated by column chromatography when methanol is used as eluent. We present results of a single crystal X-ray analysis of one of the E-isomers, which equilibrate in solution as well as in the solid state. Heating of the indazole–indole spiro compounds results in the formation of quinazolines by a ring-cleavage/ring-closure sequence (X-ray analysis). Results of DFT calculations are presented.

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36

Hu, Bin-Yuan, Da-Peng Qin, Shao-Xiang Wang, Jing-Jing Qi y Yong-Xian Cheng. "Novel Terpenoids with Potent Cytotoxic Activities from Resina Commiphora". Molecules 23, n.º 12 (7 de diciembre de 2018): 3239. http://dx.doi.org/10.3390/molecules23123239.

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A novel sesquiterpene dimer, spirocommiphorfuran A (1); two new cadinane sesquiterpenoids, commiphorenes A (2) and B (3); along with three known terpenoids (4–6), were isolated from Resina Commiphora. The structures of these new compounds were characterized by NMR, HRESIMS, quantum chemical computation, and X-ray diffraction analysis. Compound 1 features a 7-oxabicyclo[2.2.1]heptane-2-ene core, representing the first example of germacrane-type sesquiterpene dimer fused via a spiro ring system. Compound 2 is a novel sesquiterpene with a completely new carbon skeleton, which is characteristic of an additional carbon attaching to the cadinane backbone via a carbon–carbon bond. Additionally, compounds 2 and 4 exert acceptable cytotoxicity toward normal cells and high selectivity in cancer cells, especially in HepG2 cells.

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37

Bando, Masayoshi, Yuki Mizukami, Kiyohiko Nakajima, Zhiyi Song y Tamotsu Takahashi. "Formation of a spiro compound via coupling of a cyclopentadienyl ligand with a diene moiety of titanacyclopentadiene". Dalton Transactions 46, n.º 47 (2017): 16408–11. http://dx.doi.org/10.1039/c7dt03789a.

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38

Sharma, Sakshi, Goutam Brahmachari, Rajni Kant y Vivek K. Gupta. "One-pot green synthesis of biologically relevant novel spiro[indolin-2-one-3,4′-pyrano[2,3-c]pyrazoles] and studies on their spectral and X-ray crystallographic behaviors". Acta Crystallographica Section B Structural Science, Crystal Engineering and Materials 72, n.º 3 (13 de mayo de 2016): 335–43. http://dx.doi.org/10.1107/s2052520616005060.

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Synthesesviagreen route and single-crystal X-ray structural investigations have been carried out for three spiro[indolin-2-one-3,4′-pyrano[2,3-c]pyrazole] derivatives, 6′-amino-2-oxo-3′-propyl-2′H-spiro[indoline-3,4′-pyrano[2,3-c]pyrazole]-5′-carbonitrile dimethyl sulfoxide monosolvate (5a), 6′-amino-5-fluoro-2-oxo-3′-propyl-2′H-spiro[indoline-3,4′-pyrano[2,3-c]pyrazole]-5′-carbonitrile dimethyl sulfoxide monosolvate (5b) and methyl 6′-amino-5-cyano-1-methyl-2-oxo-3′-propyl-2′H-spiro[indoline-3,4′-pyrano[2,3-c]pyrazole]-3′-carboxylate 0.25 hydrate (5c), respectively. Compounds (5a) and (5b) crystallize in the triclinic space group P\bar 1, whereas compound (5c) crystallizes in the monoclinic space groupC2/c. In molecules (5a) and (5b) all the rings are practically flat, while in (5c), the heterocyclic pyran ring adopts a flattened-boat conformation. In (5a) and (5b) the cyanide group is oriented in a (−ap)conformation, while the amino group is oriented in a (+ap)conformation with a pyran ring, but in (5c) both the cyanide and amino groups are oriented in a (−ap) conformation with the pyran ring. In the crystal structure of (5a) and (5b), the molecules are linked by an elaborate system of N—H...O and N—H...N hydrogen bonds to generate a zigzag-like construct. In (5c) molecules are linked by N—H...O hydrogen bonds, thereby generating extended chains. The present communication focuses on the detailed and comparative information about spectral behaviors, single-crystal X-ray crystallographic properties and solid-state supramolecular architectures of these synthesized compounds of potential biological interests.

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39

Tong, Junjie, Yang Zhang, Yang Xu, Yangyang Han, Chuan Li, Wenying Zhuang y Yongsheng Che. "Spirocitrinols A and B, citrinin derivatives with a spiro[chromane-2,3′-isochromane] skeleton from Penicillium citrinum". RSC Advances 13, n.º 9 (2023): 6124–29. http://dx.doi.org/10.1039/d3ra00665d.

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Two new citrinin-derived metabolites spirocitrinols A (1) and B (2) with a spiro[chromane-2,3′-isochromane] skeleton were isolated from cultures of Penicillium citrinum. Compound 1 showed moderate cytotoxicity towards human tumor cells.

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40

Rether, Jan, Gerhard Erkel, Timm Anke y Olov Sterner. "Inhibition of inducible TNF-α expression by oxaspirodion, a novel spiro-compound from the ascomycete Chaetomium subspirale". Biological Chemistry 385, n.º 9 (1 de septiembre de 2004): 829–34. http://dx.doi.org/10.1515/bc.2004.108.

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Abstract In a search for compounds inhibiting the inducible TNF-αa promoter activity in T cells, a new spiro-compound, designated oxaspirodion, was isolated from fermentations of the ascomycete Chaetomium subspirale. Oxaspirodion inhibited TNF-α promoter-driven luciferase reporter gene expression with an IC50 value of 2.5 µg/ml (10 µM) in TPA/ionomycin-stimulated Jurkat T cells. Studies on the mode of action of the compound revealed that the inhibition of the TNF-α promoter activity is caused by an inhibition of the phosphorylation of the ERK1/2 kinases. In addition, oxaspirodion inhibited the activation of the transcription factor NF-κB, which is involved in the inducible expression of many proinflammatory genes.

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41

Tan, Xiaojun y Xiuhui Lu. "Ab initio study of the mechanism of formation of a spiro-Sn-heterocyclic ring compound by the cycloaddition reaction of H2C=Sn: and ethylene". Journal of the Serbian Chemical Society 84, n.º 3 (2019): 293–301. http://dx.doi.org/10.2298/jsc180603072t.

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X2C=Sn: (X = H, Me, F, Cl, Br, Ph, Ar?) are new species of chemistry. The cycloaddition reactions of X2C=Sn: is a new study field of stannylene chemistry. The mechanism of cycloaddition reaction of singlet H2C=Sn: with ethylene is studied for the first time using the MP2/GENECP (C, H in 6-311++G**; Sn in LanL2dz) method in this paper. From the potential energy profile, it could be predicted that the reaction has one dominant reaction channel. The reaction rule presented is that the 5p unoccupied orbital of tin in H2C=Sn: sidewise overlaps with the bonding ? orbital of ethylene resulting in the formation of an intermediate. The instability of the intermediate makes it isomerise to a four-membered ring stannylene. As the 5p unoccupied orbital of the Sn atom in the four-membered ring stannylene and the ? orbital of ethylene form a ??p donor?acceptor bond, the four-membered ring stannylene further combines with ethylene to form another intermediate, and this intermediate further isomerises to a spiro-Sn-heterocyclic ring compound. The Sn in the spiro-Sn-heterocyclic ring compound is combined with adjacent atoms by sp3 hybridization. The results of this study reveal the mechanism of cycloaddition reaction of X2C=Sn: with symmetric ?-bond compounds.

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42

Lutz, Marlon R., Matthias Zeller y Daniel P. Becker. "2,3,5′,6,6′,7-Hexamethoxy-3′H,10H-spiro[anthracene-9,1′-isobenzofuran]-3′,10-dione". Acta Crystallographica Section E Structure Reports Online 63, n.º 11 (24 de octubre de 2007): o4390—o4391. http://dx.doi.org/10.1107/s1600536807051136.

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The title molecule, C27H24O9, was formed via a transannular electrophilic addition of a putative cyclotriveratrylene triketone and is made up of an anthrone and an isobenzofuranone ring that are connected via one C atom to form a spiro compound. The anthracene and isobenzofuranone ring systems of the spiro compound are both essentially planar and perpendicular to each other, with an angle of 89.90 (2)° between them. The rigid molecule crystallizes with large voids of 598.7 Å3, or 21.5% of the unit-cell volume, that are partially filled with unmodelled disordered solvent molecules. The voids stretch as infinite channels along the [101] direction. The packing of the structure is partially stabilized by a range of weak C—H...O hydrogen bonds and also by C—H...π interactions. No significant π–π interactions are present in the crystal structure.

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43

Zhang, Xiu-Ling, Ai-Zhen Liu y Mei-Fang Jin. "1′-Methyl-4′-(1-naphthyl)-1H-indole-3-spiro-2′-pyrrolidine-3′-spiro-2′′-thiazolo[3,2-a]benzimidazole-2(3H),3′′(2′′H)-dione". Acta Crystallographica Section E Structure Reports Online 62, n.º 7 (23 de junio de 2006): o2961—o2962. http://dx.doi.org/10.1107/s1600536806022847.

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In the title compound, C30H22N4O2S, two spiro junctions link a planar 2-oxoindole ring, a pyrrolidine ring and a thiazolo[3,2-a][1,3]benzimidazol-3-one system. Molecules form dimers connected by N—H...N hydrogen bonds.

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44

Ma, Xican, Bing Han, Aoyu Wang, Lu Yang, Menghao Huang, Kushan Chowdhury, Jian Gu, Kai Zhang y Kai Lv. "Identification of benzothiazones containing a hexahydropyrrolo[3,4-c]pyrrol moiety as antitubercular agents against MDR-MTB". RSC Advances 10, n.º 24 (2020): 14410–14. http://dx.doi.org/10.1039/d0ra00750a.

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IMB1603, a spiro-benzothiazone compound discovered by our lab, displayed potent anti-MTB activity in vitro and in vivo. In this study, benzothiazones containing a hexahydropyrrolo[3,4-c]pyrrol moiety were synthesized and evaluated based on IMB1603.

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45

van der Haas, Richard, Jeroen Dekker, Jorma Hassfeld, Anastasia Hager, Peter Fey, Philipp Rubenbauer y Eric Damen. "Synthesis and Properties of 2-Oxa-6-azaspiro[3.3]heptane Sulfonate Salts". Synthesis 49, n.º 11 (2 de marzo de 2017): 2394–401. http://dx.doi.org/10.1055/s-0036-1588733.

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An improved synthesis of the bicyclic spiro compound 2-oxa-6-azaspiro[3.3]heptane is presented. While this compound is often isolated as an oxalate salt, its isolation as a sulfonic acid salt yields a more stable and more soluble product. With these improved properties access to a wider range of reaction conditions with the spirobicyclic 2-oxa-6-azaspiro[3.3]heptane has been enabled.

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46

Sennikova, Valeriia V., Alena V. Zalaltdinova, Yulia M. Sadykova, Ayrat R. Khamatgalimov, Almir S. Gazizov, Alexandra D. Voloshina, Anna P. Lyubina et al. "Diastereoselective Synthesis of Novel Spiro-Phosphacoumarins and Evaluation of Their Anti-Cancer Activity". International Journal of Molecular Sciences 23, n.º 22 (18 de noviembre de 2022): 14348. http://dx.doi.org/10.3390/ijms232214348.

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Herein we present the regio- and diastereoselective synthesis of novel pyrrolidine-fused spiro-dihydrophosphacoumarins via intermolecular [3 + 2] cycloaddition reaction. The presented approach is complementary to existing ones and provides an easy entry to the otherwise inaccessible derivatives. Additionally, the unprecedented pathway of the reaction of 4-hydroxycoumarin with azomethine ylides is described. The anti-cancer activity of the obtained compounds was tested in vitro, the most potent compound being 2.6-fold more active against the HuTu 80 cell line than the reference 5-fluorouracil, with a selectivity index > 32.

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47

Zhang, Yu-Hua, Xiao-Hui Wang, Shan Liu y Cheng Yao. "3,9-Bis(2-hydroxy-2-propyl)-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane 3,9-dioxide hemihydrate". Acta Crystallographica Section E Structure Reports Online 62, n.º 7 (9 de junio de 2006): o2620—o2621. http://dx.doi.org/10.1107/s1600536806020605.

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In the crystal structu of the title compound, C11H22O8P2·0.5H2O, the asymmetric unit contains two spiro[5.5]undecane molecules and one water molecule. The structure is stabilized by intra- and intermolecular C—H...O and O—H...O hydrogen bonds.

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48

Vrábel, Viktor, Július Sivý, Ľubomír Švorc, Jan Světlík y Šafař Peter. "Crystal and electronic structure, N–H⋯N and C–H⋯O interactions in novel spiro-[chroman-chromene]-carboxylate". Acta Chimica Slovaca 10, n.º 1 (25 de abril de 2017): 74–78. http://dx.doi.org/10.1515/acs-2017-0013.

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Abstract We report here the structure of new spiro-derivative, namely methyl (2R,4R)-4-(5-methylthiazol- 2-ylamino)spiro[chroman-2,2’-chromene]-3’-carboxylate, C23H20N2O4S, which crystallizes as racemate in the space group P-1. In this compound, the chromanone moiety consists of a benzene ring fused with a sixmembered heterocyclic ring which adopts a distorted half-chair conformation. The molecules are linked by a combination of N–H⋯N hydrogen bonds and weak C–H⋯O, C-H⋯S, C-H⋯π, inter- and intramolecular interactions resulting in a two-dimensional network in the crystal structure.

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49

Dastoorani, Parvaneh, Mohammad A. Khalilzadeh, Fatemeh Khaleghi, Malek Taher Maghsoodlou, Werner Kaminsky y Ali Shokuhi Rad. "Experimental and computational studies on the synthesis of diastereoselective natural-based Meldrum spiro dibenzofuran derivatives". New Journal of Chemistry 43, n.º 17 (2019): 6615–21. http://dx.doi.org/10.1039/c9nj00766k.

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Herein, a novel route to achieve chiral Meldrum spiro dibenzofuran derivatives was developed, which involved a 2,2-dimethyl-1,3-dioxane-4,6-dione (Meldrum's acid)-mediated Knoevenagel reaction of substituted aryl halides, followed by a Diels–Alder reaction with euparin as a natural compound.

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50

Engelhardt, Udo y Ursula Diefenbach. "Notizen: Cyclotriphosphazen-2-spiro-3′ -cyclodi[phosphadiazan] — Eine Spiroverbindung aus Hexachlortriphosphazen und Dihydrazidothiophosphorsäure-O-phenylester / Cyclotriphosphazene-2-spiro-3′-cyclodi[phosphadiazane] — A Spiro Compound from Hexachlorocyclotriphosphazene and Dihydrazidothiophosphoric Acid 0-Phenylester". Zeitschrift für Naturforschung B 44, n.º 5 (1 de mayo de 1989): 612–14. http://dx.doi.org/10.1515/znb-1989-0518.

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Hexachlorocyclotriphosphazene (Cl2P=N)3 reacts with dihydrazidothiophosphoric acid 0-phenylester C6H5O—P(=S)(NH—NH2)2 in THF in the presence of triethylamine at room temperature to give the spirocyclic title compound, whose constitution has been confirmed by MS, IR, 31P NMR and elemental analysis.

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