Dissertations / Theses on the topic 'Benzodioxine'

Au cours de ce travail, nous nous sommes intéressés à la synthèse de composés biologiquement actifs. Dans un premier temps, nous avons étudié la déshydratation des macrocarpals A et B en vue d’obtenir un accès semi-synthétique rapide au macrocarpal G qui possède des propriétés anorexigèniques.Dans un second temps, nous avons développé une nouvelle synthèse énantiosélective du Lévomilnacipran qui est un antidépresseur qui vient de recevoir son autorisation de mise sur le marché aux Etats-Unis et au Canada. Cette synthèse de novo nous a permis d’obtenir le produit actif en neuf étapes avec un rendement global de 32 % et un excès énantiomérique conservé de 88 %. Nous avons ensuite mis au point une synthèse énantiosélective du 1,4-benzodioxane F17807. Cette synthèse en quatre étapes repose sur une étape clé de SNAr du (S)-isopropylidèneglycerol sur un fluorophénol. Cette étape permet d’introduire l’information chirale qui sera maintenue tout au long de la synthèse puisque le produit final est isolé avec un excès énantiomérique de 98 %.Nous avons également synthétisé des analogues du dérivé d’épipodophyllotoxine, F14512. Ces stéréoisomères sont des impuretés qui peuvent apparaitre dans la formulation finale du principe actif. Pour finir, nous avons imaginé de nouvelles formulations nanométriques du composé F14512 afin que celui-ci s’auto-assemble en micelle. Pour cela, quatre amphiphiles ont été synthétisés et les premiers tests montrent une internalisation préférentielle au niveau des tumeurs ou des cellules surexprimant le STP en fonction de leur fonctionnalisation
This thesis deals with the synthesis of biologically active compounds. In the first chapter, we developed a semi-synthetic process for the exo-dehydration of macrocarpals A and B to get access to macrocarpal G which is a drug known for its anorexigenic activity. The second chapter is dealing with the enantioselective synthesis of the anti-depressive drug Levomilnacipran which has recently been approved by the FDA. This de novo synthesis was performed in 9 steps with an overall yield of 32 % and with an enantiomeric excess of 88 % which was maintained throughout our synthesis. In the third chapter we worked on a novel route for the enantioselective synthesis of the antipsychotic drug F17807. Our four-step synthesis of the 1,4-benzodioxan unit relied, as the key step, on the SNAr reaction of optically active (S)-isopropylidenglycerol on a properly functionalized fluorophenol and subsequent transformations. F17807 was produced with an ee of 98%.The fourth chapter reports our investigations for the synthesis of three stereoisomers of F14512 which is a targeted epipodophyllotoxin-based anticancer drug.Finally, new nanometric formulations of F14512 were designed in the fifth chapter. Four different drug-containing amphiphilic compounds were synthesized, assembled into the corresponding micelles, and evaluated as delivery systems. Preliminary in vitro and in vivo results indicate that the nanomicelles are highly promising for the targeting of tumors as visualized by fluorescence imaging

La cycloaddition dipolaire 1,3 des diarylnitrilimines sur le benzodioxinne-1,4 carboxylate-2 d'ethyle conduit a des cycloadduits qui apres ouverture donnent des derives de l'aryloxy-4 diphenyl-1,3 pyrazole qui ne sont pas accessibles par une methode classique de synthese de pyrazoles

Les maladies cardio-vasculaires representent la premiere cause de mortalite dans les pays industrialises. De nombreuses enquetes epidemiologiques ont mis en evidence le lien existant entre un taux eleve de cholesterol dans le sang et le risque d'accidents ischemiques. Cependant, un autre facteur, tout aussi consequent, la peroxydation ou auto-oxydation des lipides, doit etre pris en consideration. Pour inhiber un tel phenomene l'usage d'antioxydants se revele necessaire. Dans le cadre de la mise en uvre d'une nouvelle therapeutique concernant certaines maladies cardio-vasculaires, la preparation de molecules 1,4-benzodioxiniques et 1,4-benzodioxaniques a activite mixte, hydroxylees ou aminees en position 6 ou 7 sur l'homocycle et substituees en position 2 par une fonction amide ou amine, a ete envisagee. Pour acceder a ces composes, nous avons consacre, une grande part de notre travail a la fonctionnalisation regioselective en position 6 et 7 des heterocycles 1,4-benzodioxiniques et 2,3-dihydro-1,4-benzodioxiniques substitues en position 2, en etudiant plus en detail les reactions de substitutions electrophiles de type de friedel et crafts. Plusieurs voies de synthese distinctes ont ainsi ete mises au point afin d'acceder aux acides benzodioxaniques et benzodioxiniques d'une part regioselectivement hydroxyles en c#6 ou c#7 et d'autre part regioselectivement amines en c#6. A partir de ces differents substrats, divers carboxamides et derives aminomethyles ont ete prepares. Les etudes pharmacologiques realisees sur ces composes ont fait apparaitre d'interessantes proprietes antioxydantes vis a vis de la protection de la peroxydation lipidique ainsi que de notables proprietes anticalciques et hypolipemiantes. Par ailleurs, en vue de preparer ulterieurement, les analogues benzodioxaniques du trolox et de ses analogues, nous avons developpe la synthese generale de composes benzodioxaniques doublement substitues en position 2, au depart des hemiacetals correspondants

This thesis deals with the synthesis of electroactiveorganic compounds. The synthesis of ethylenedioxy-benzodioxinstri-dioxin and tetra-dioxin are described. These molecules wereprepared with the aim of creating donor molecules for cationicradical salts. The symmetric analogs of tri-dioxin,methylenedioxy-derivative and ethylenedioxy-naphthalene werealso synthesized. Three different cation radical salts with 2:1stoichiometries were obtained from tri-dioxin, whiletetra-dioxin merely provided polycrystalline materials.Tri-dioxin and tetra-dioxin were also successful as operationalmatrixes in PALDI-TOF.

Tetrathiafulvalenes with the2-dialkyl-amino-1,3-dithiolium-4-thiolate mesoion asbuilding-block was also synthesized. A series of doublyalkylthiol-substituted TTFs were prepared with the aim offorming self-assembly monolayers on gold surfaces in theapplication of organic thin film field-effect transistors.Film-formation for two TTFs were studied and they providedrelatively dense packed monolayers with a discrete distance ofthe TTF moiety from the gold surface.

The mesoionic compound was also for the first time used inanumpolungreaction. The electrophile obtained in situ bytreatment of mesoion with sulfuryl chloride was reacted with avariety of electron-rich aromatic compounds. From the receivedproducts three new arylthio-substituted TTFs weresynthesized.

Keywords:Synthesis, Benzodioxin, Tetrathiafulvalene,Mesoion, Organic Conductor, Cation Radical Salt, CyclicVoltammetry, Electrocrystallization, Self-Assembly Monolayer,SAM, Organic Field-Effect Transistor, OFET

Notre memoire comporte cinq chapitres regroupes en deux grandes parties : l'une relative a la preparation et la reactivite dans des reactions de transfert monoelectronique de substrats nitro-heterocycliques, l'autre a la valorisation biologique des intermediaires precedemment synthetises. La premiere partie de ce travail decrit l'extension du mecanisme de substitution radicalaire nucleophile unimoleculaire (s#r#n1) en series 6-nitrobenzo1,3dioxole et 7-nitro-2,1,3-benzothiadiazole par une etude mecanistique complete et une generalisation a divers anions nitronates ou malonates. Dans la seconde partie, environ 50 molecules ont ete synthetisees par des reactions classiques de synthese organique (formation d'aldimines, d'hydrazones, reaction de knoevenagel) a partir des intermediaires necessaires a la synthese des molecules cibles decrites precedemment et ont ete soumises a des tests antiparasitaires. Ainsi par exemple, la fonctionnalisation du 5-benzo1,3dioxol-5-yl-1-methyl-1h-imidazole-2-carboxaldehyde conduit a de nouveaux composes possedant une activite leishmanicide superieure a celle de la pentamidine, produit de reference.

Étude des propriétés complexantes et de la capacité d'extraction des produits préparés. Les ionophores, du grec : ion et phore, transporteur, possèdent la propriété de former des complexes avec une grande variété de cations. Nous avons voulu dans ce mémoire, rapporter la synthèse de tels composés. Ainsi avons nous obtenu des ionophores présentant un motif benzodioxinique, et d'autres sans ce motif. Ces produits ont fait l'objet de tests de dissociations acide dans le méthanol, de complexation du sodium et du potassium dans le méthanol, et d'extraction de ces mêmes cations en milieu hétérogène. Cette synthèse nous a également livré des tensioactifs dont les propriétés ont été mises en évidence

L'utilisation des complexes organometalliques, en particulier, ceux du palladium(o) connait un essor considerable depuis les annees 1970 ; elle permet en effet la realisation d'un grand nombre de reactions, notamment des reactions d'heterocyclisation, dans des conditions souvent douces avec des chimio-, des regio- et des diastereoselectivites remarquables. Il apparait donc clairement que le defi a l'heure actuelle est de realiser ces reactions de facon enantioselective. C'est donc dans cette optique que ce sont inscrits mes travaux de these. Des resultats anterieurs avaient montre que la synthese d'ethers allyliques, par reaction de o-alkylation intermoleculaire de carbonates allyliques par des phenols, s'effectuait avec de bons rendements. Nous avons donc mis a profit ces resultats en developpant cette reaction en serie intramoleculaire. Dans un premier temps, nous avons mis au point la reaction tandem mettant en jeu un dicarbonate allylique et des nucleophiles ambidents. Nous avons montre que l'acces a des heterocycles azotes et oxygenes etait possible, en presence d'une quantite catalytique de palladium(o) associe a une phosphine bidente, le 1,4-diphenylphosphinobutane (dppb). Nous avons ensuite etendu cette reaction de cyclisation en serie chirale et des benzodioxanes, des benzomorpholines et des benzopiperazines enantiomeriquement enrichis ont ete obtenus. L'influence de la geometrie du ligand chiral, de la temperature, du solvant et de la nature du nucleophile sur l'enantioselectivite de la reaction a ete largement mis en avant. Nous avons alors montre qu'un choix judicieux de ces differents parametres, nous a permis de synthetiser des benzomorpholines avec des exces enantiomeriques de 79%. Nous avons ensuite aborde l'aspect mecanistique de cette cyclisation et nous avons etabli que l'attaque nucleophile intramoleculaire n'etait vraisemblablement pas l'etape enantioselective, infirmant ainsi les resultats decrits dans la litterature.

Pharmaceutical Sciences
Ph.D.
The acetylcholine (ACh) receptor system belongs to rhodopsin GPCR family and is an integral membrane protein divided into two types: muscarinic and nicotinic. The naturally occurring neurotransmitter acetylcholine binds to these two receptor systems non- selectively. The regulatory effects of the neurotransmitter acetylcholine are diverse ranging from autonomic nervous system and the central nervous system through different types of neurons innervated by cholinergic inputs. Muscarinic acetylcholine receptors (mAChRs) are divided into five receptor subtypes (M1-M5). In general, M1, M3 and M5 receptor subtypes are coupled via Gq like proteins; while M2 and M4 subtypes are coupled to Gi-proteins. Muscarinic receptors are widely distributed in the body where they mediate a variety of important physiological effects. mAChRs have been the target of drug development efforts for the treatment of various disorders including overactive bladder, Alzheimer's disease, pain, cognitive impairment, dr
Temple University--Theses

Pharmaceutical Sciences
Ph.D.
The acetylcholine (ACh) receptor system belongs to rhodopsin GPCR family and is an integral membrane protein divided into two types: muscarinic and nicotinic. The naturally occurring neurotransmitter acetylcholine binds to these two receptor systems non- selectively. The regulatory effects of the neurotransmitter acetylcholine are diverse ranging from autonomic nervous system and the central nervous system through different types of neurons innervated by cholinergic inputs. Muscarinic acetylcholine receptors (mAChRs) are divided into five receptor subtypes (M1-M5). In general, M1, M3 and M5 receptor subtypes are coupled via Gq like proteins; while M2 and M4 subtypes are coupled to Gi-proteins. Muscarinic receptors are widely distributed in the body where they mediate a variety of important physiological effects. mAChRs have been the target of drug development efforts for the treatment of various disorders including overactive bladder, Alzheimer's disease, pain, cognitive impairment, drug addiction, schizophrenia and Parkinson's disease. The development subtype selective ligands possess a challenge due to a high degree of homology among mAChR subtypes, however the recent availability of the X-ray crystal structure for the M2 and M3 receptor can be utilized for the design of new ligands. The pharmacophoric requirements for cholinergic ligands have been reported by numerous investigators based on structure-activity relationship (SAR) and/or molecular modeling data of known muscarinic ligands. These fundamental requirements are useful when designing muscarinic ligands but have provided little guidance in the design of subtype selective compounds. Our interest in developing novel muscarinic receptor ligands led to the design of lactone-based ligands using an approach similar to that reported by Kaiser et al. Preliminary binding studies of our previously synthesized lactone based compounds indicated that several were nonselective, low affinity (IC50 = µM range) muscarinic agonists (based on preliminary in vivo data). Hence based on the background information, we decided to utilize the previously synthesized lactone parent compound as lead molecule set out to investigate a new series of lactone based compounds in order improve the affinity and later the selectivity of ligands. Bioisosteric approach has been investigated for the metabolic lability of the lactone ring. Four probable bioisosteres have been evaluated: tetrahydrofuran, 1,3-benzodioxole, oxazolidinone and chromone. Thermal/microwave assisted synthesis has been utilized in the generation of intermediates as well as final compounds. Preliminary screening and further evaluation (IC50/ subtype selectivity) has resulted in the identification of promising fragments as bioisosteres for the lactone ring.
Temple University--Theses

Ces travaux concernent l'etude spectroscopique du 3,4-methylenedioxybenzene (1,3-benzodioxole) et de plusieurs de ses derives dont certains sont des produits naturels (piperonal, piperine etc. . . ). Le cycle oxygene a cinq elements impose une contrainte au noyau benzenique dont les deforpmations induisent une structure alternee de type kekyle. La geometrie des diverses molecules etudiees a ete calculee a l'aide de la methode mndo. L'influence structurale de cycles a cinq elements autres que celui engendre par le groupement 3,4-methylenedioxy a ete etudiee. Ceci a permis d'evaluer le caractere, inhibant ou non, des couplages conjugatifs entre et une insaturation dans le cycle a cinq elements, sur l'alternance des longueurs de liaison au sein du noyau aromatique. Le spectre uv du groupement 1,3-benzodioxole est compose de deux bandes d'absorption dont les caracteristiques dependent a la fois de la contrainte du cycle oxygene et de la nature des substituants fixes sur le noyau benzenique. La transition, situee vers les grandes longueurs d'onde (vers 281 nm), est analogue a la transition secondaire transition b#2#ua#1#g de la molecule de benzene libre (vers 260 nm). La transition qui apparait vers de plus courtes longueurs d'onde (vers 231 nm) est une transition de transfert de charge des electrons non-liants des oxygenes vers #*. Cette transition diminue d'intensite sous la contrainte du cycle a cinq elements. Les intensites des differentes molecules etudiees ont ete expliquees sur la base de correlations avec des parametres electronqiues du groupement 1,3-benzodioxole. Le chromophore implique n'est plus le noyau benzenique diversement perturbe mais un groupement comprenant les oxygenes du cycle fusionne. En consequence, les modeles spectroscopiques applicables au chromophore benzenique ne sont plus totalement valables pour les derives du 1,3-benzodioxole

Over the recent years, increasing scientific attention has been paid to pharmaceuticals, other drugs and their metabolites. These substances are of particular interest because of their physiological, toxicological and ecotoxicological effects in the human body and respectively in the environment. Cytochrome P450 enzymes (P450s) play a key role in the conversion and detoxification of bioactive compounds including many pharmaceuticals and drugs. Most of these enzymes belong to the monooxygenases; they are intracellular and rather unstable biocatalysts that are difficult to purify and require expensive, complex cofactors, which alltogether hampers their use in isolated form. The investigations carried out here with fungal peroxygenases have shown that this enzyme sub-subclass (EC 1.11.2.x) has a promising potential for oxyfunctionalizations and can catalyze a variety of reactions typical for P450s. Peroxygenases are extracellular, i.e. secreted fungal enzymes with high stability, which merely need peroxide for function. Results obtained with the unspecific/aromatic peroxygenases (APOs) of Agrocybe aegerita, Coprinellus radians and Marasmius rotula have demonstrated that APOs catalyze numerous H2O2-dependent monooxygenations of pharmaceuticals and psychoactive drugs. Among them are i) the monooxygenation of aromatic compounds, ii) the benzylic hydroxylation of toluene derivatives, iii) the O-dealkylation of different ether structures including the scission of benzodioxoles (O-demethylenation) and esters as well as iv) the N-dealkylation of secondary and tertiary amines. The peroxygenases studied considerably differ in their substrate spectrum and the preferred positions of oxidation. This finding opens the possibility to develop in the future an “enzymatic toolbox“ on the basis of fungal peroxygenases for the oxyfunctionalization of pharmaceutically relevant compounds. Mechanistic studies showed that (1) the monooxygenations always proceed via incorporation of one oxygen atom from the peroxide, (2) the demethylation of phenacetind1 established a deuterium isotope effect similar to P450s, (3) the catalytic efficiencies for the studied oxidations are in the same range as those of P450s (though the kcat- and Km values are noticeably higher), (4) the kinetic studies with nitro-1,3-benzodioxole gave parallel double reciprocal plots suggestive of a “ping pong” mechanism, (5) the substrate spectrum and the activity pattern of APOs follows in a wide range those of the human key P450s as well as that (6) the difference spectra obtained in bindings studies are of the phenol type of P450s. Furthermore, APOs were found to be stable and active in long term experiments over two weeks and they oxidized pharmaceuticals at low, environmentally relevant concentration (ppb range). All the above properties strongly indicate that APOs respresent an interesting alternative for the enzymatic conversion of pharmaceuticals as well as for the preparation of human drug metabolites, for example, in medicinal and pharmacological research or the bioremediation sector (removal of pharmaceuticals from environmental media)
In den letzten Jahren sind Pharmazeutika und deren Metabolite mehr und mehr in den Fokus der Wissenschaft gerückt. Diese Substanzen sind aufgrund ihrer physiologischen und toxikologischen sowie ökotoxikologischen Wirkungen im menschlichen Körper bzw. in der Umwelt von besonderem Interesse. Cytochrom-P450-Enzyme (P450s) spielen eine Schlüsselrolle bei der Umsetzung und Detoxifizierung bioaktiver Substanzen, darunter vieler Pharmazeutika und Drogen. Es handelt sich bei diesen Enzymen in erster Linie um Monooxygenasen, die intrazellulär lokalisiert und relativ instabil sind; sie benötigen komplexe, teure Kofaktoren und sind nur unter hohem Aufwand zu reinigen, was ihre Anwendung in isolierter Form insgesamt erschwert. Die hier durchgeführten Untersuchungen zu pilzlichen Peroxygenasen haben gezeigt, dass diese Enzymsubklasse (EC 1.11.2.x) ein hohes Oxyfunktionalisierungspotenzial besitzt und eine Vielzahl P450-typischer Reaktionen zu katalysieren vermag. Peroxygenasen sind extrazelluläre, d.h. sekretierte Pilzenzyme, die eine hohe Stabilität aufweisen und lediglich ein Peroxid als Kosubstrat benötigen. Die unter Verwendung der unspezifischen/aromatischen Peroxygenasen (APOs) von Agrocybe aegerita, Coprinellus radians und Marasmius rotula gewonnenen Ergebnisse belegen, dass APOs verschiedene H2O2-abhängige Monooxygenierungen von Pharmazeutika und psychoaktiven Substanzen realisieren. Dazu gehören i) die Monooxygenierung von Aromaten, ii) die benzylische Hydroxylierung von Toluolderivaten, iii) die O-Dealkylierung verschiedener Etherstrukturen einschließlich der Spaltung von Benzodioxolen (O-Demethylenierung) und Estern sowie iv) die N-Dealkylierung von sekundären und tertiären Aminen. Die untersuchten Peroxygenasen wiesen teilweise deutliche Unterschiede im Substratspektrum und den präferierten Oxidationspositionen auf. Dieser Befund eröffnet die Möglichkeit, zukünftig einen „enzymatischen Werkzeugkasten“ auf Basis pilzlicher Peroxygenasen für die Oxyfunktionalisierung von pharmazeutisch relevanten Wirkstoffen zu entwickeln. Mechanistische Experimente zeigten, dass (1) die Monooxygenierungen stets unter Einbau eines aus dem Peroxid stammenden Sauerstoffatoms erfolgen, (2) die Deethylierung von Phenacetin-d1 einen Deuteriumisotopeneffekt ähnlich dem der P450s aufweist, (3) die katalytischen Effizienzen für die untersuchten Oxidationen im gleichen Bereich wie die der P450s liegen (wobei die kcat- und Km-Werte deutlich höher ausfallen), (4) die kinetischen Untersuchungen zur Oxidation von Nitro-1,3-Benzodioxol parallele Verläufe der ermittelten Ausgleichsgeraden in der doppelt reziproken Darstellung ergaben, was für einen “Ping-Pong-Mechanismus“ spricht, (5) sich das Substratspektrum und die Aktivitätsmuster der APOs in einem weiten Bereich mit denen der wichtigsten menschlichen P450s decken sowie dass (6) die in Bindungsstudien gewonnenen Differenzspektren denen des Phenoltyps der P450s entsprechen. Desweiteren erwiesen sich APOs in Langzeitexperimenten über zwei Wochen als stabil und aktiv und sie waren in der Lage, Pharmazeutika in umweltrelevanten Konzentrationen (ppb-Bereich) zu oxidieren. All die genannten Eigenschaften legen nahe, dass APOs eine interessante Alternative zur enzymatischen Umsetzung von Pharmazeutika sowie zur Herstellung von humanen Pharmazeutika-Metaboliten darstellen, die z.B. Einsatz in der medizinischpharmakologischen Forschung oder im Umweltbereich (Entfernung von Pharmazeutika aus Umweltmedien) finden könnten

Synthèse de composés à structure benzodioxinique porteurs de groupes pharmacophores alpha et bêta-bloquants. →Synthèse des composés du type B possédant le motif pipéridinométhyle du pipéroxane. Synthèse des composés du type E et du type F possédants le motif N-(diméthoxy-3,6 phénoxyéthyl) aminométhyle du WB4101

Approche de la synthèse d'alcaloïdes derivés de dioxolo-1,3 (4,5-J) phénanthridine : la première partie traite de quelques analogues non cyclisés (synthèse et étude de l'activité anticancéreuse) ; la deuxième partie résume les différents essais de synthèse totale de ces alcaloïdes et particulièrement de l'O-acétyl-2 DI-O-benzyl-3,4 désoxo lycoricidine

Synthèse de dérivés dihydroaryles ortho-substitués en particulier par un groupe aldéhyde. Obtention par l'addition de diels-alder entre dienamines acycliques conjuguées et aldéhydes insaturés. Elle s'effectue avec de très bonnes régiosélectivité et stéréospécificité. L’inhibition des acétylcholinestérases par ces dihydrobiaryles se situe au niveau du carbofurane et de la néostigmine. Étude d'un écosystème termite-fourmi. Les relations entre termites de différents genres et entre termites et fourmis font intervenir les composes présents dans la cuticule. La spectrométrie de masse a été l'outil utilisé avec la mise au point d'un nouveau gaz d'ionisation chimique: l'oxyde d'éthylène.

Yes
An efficient four-step synthesis of tetracyclic lactones from 1,4-benzodioxine-2-carboxylic acid was developed. Ellipticine derivatives exhibit antitumor activity however only a few derivatives without carbazole subunit have been studied to date. Herein, several tetracyclic lactones were synthesized and biologically evaluated. Several compounds (2a, 3a, 4a and 5a) were found to be inhibitors of the Kras-Wnt pathway. The lactone 2a also exerted a potent inhibition of Tau protein translation and was shown to have capacity for CYP1A1-bioactivation. The results obtained are further evidence of the therapeutic potential of tetracyclic lactones related to ellipticine. Molecular modeling studies showed that compound 2a is inserted between helix α3 and α4 of the KRas protein making interactions with the hydrophobic residues Phe90, Glu91, Ile9364, Hie94, Leu133 and Tyr137and a hydrogen bond with residue Arg97.
The Spanish Minister (CTQ2011-29285-C02-02) the SGR(2014)-1017 Generalitat de Catalunya and the Laboratories Servier (France)

博士
東海大學
化學系
102
Antrodia camphorata (AC) is a medicinal mushroom that grows on the inner heartwood wall of Cinnamomum kanehirai Hay (Lauraceae), an endemic species that is used in Chinese medicine for its anti-tumor and immunomodulatory properties. In this study, we concentrated that a possible active compound SY-1 which contained in all three different sources of Antrodia camphorata was further collected using preparative high performance liquid chromatography. The purified compound was confirmed as 4,7-dimethoxy-5-methyl-l,3-benzodioxole using ultraviolet, mass spectroscopy and nuclear magnetic resonance analyses. SY-1 profoundly decreased the proliferation of human colon cancer cells (COLO 205) through G0/G1 cell-cycle arrest (50–150 mM) and induction of apoptosis (>150 mM). Cell-cycle arrest induced by SY-1 was associated with a significant increase in levels of p53, p21/Cip1 and p27/Kip1, and a decrease in cyclins D1, D3 and A. In contrast, SY-1 treatment did not induce significant changes in G0/G1 phase cell-cycle regulatory proteins in normal human colonic epithelial cells (FHC). Thecells were cultured in soft agar to evaluate anchorage-independent colony formation, and we found that the number of transformed colonies was significantly reduced in the SY-1-treated COLO 205 cells. These findings demonstrate, for the first time, that SY-1 inhibits human colon cancer cell proliferation through inhibition of cell growth and anchorage-independent colony formation in soft agar. A set of ten 4,7-dimethoxy-l,3-benzodioxole derivatives based on a lead compound previously discovered by our group, SY-1, which was isolated from Antrodia camphorata, were evaluated for their in vitro inhibitory activity on human colorectal carcinoma cells (COLO 205). Structure–activity relationship studies of the 10 compounds indicated the importance of the chain length of thealkyl group at the 5-position, and the 2-propenyl substituent named ‘apiole’ exhibited the most potent inhibitory activity. In the present study, we demonstrate that the SY-1 analogue ‘apiole’ decreased the proliferation of COLO 205 cells, but not that of normal human colonic epithelial cells (FHC). The G0/G1 cell cycle arrest induced by apiole (75–225 mM) was associated with significantly increased levels of p53, p21 and p27 and decreased levels of cyclin D1. Concerning COLO 205 cell apoptosis, apiole (>150 mM) treatment significantly increased the levels of cleaved caspases 3, 8, 9 and bax/bcl-2 ratio and induced ladder formation in DNA fragmentation assay and sub-G1 peak in flow cytometry analysis. These findings suggest that SY-1 and apiole can suppress COLO 205 cell growth; however, the detailed mechanism of these processes require further investigation.

Over the recent years, increasing scientific attention has been paid to pharmaceuticals, other drugs and their metabolites. These substances are of particular interest because of their physiological, toxicological and ecotoxicological effects in the human body and respectively in the environment. Cytochrome P450 enzymes (P450s) play a key role in the conversion and detoxification of bioactive compounds including many pharmaceuticals and drugs. Most of these enzymes belong to the monooxygenases; they are intracellular and rather unstable biocatalysts that are difficult to purify and require expensive, complex cofactors, which alltogether hampers their use in isolated form. The investigations carried out here with fungal peroxygenases have shown that this enzyme sub-subclass (EC 1.11.2.x) has a promising potential for oxyfunctionalizations and can catalyze a variety of reactions typical for P450s. Peroxygenases are extracellular, i.e. secreted fungal enzymes with high stability, which merely need peroxide for function. Results obtained with the unspecific/aromatic peroxygenases (APOs) of Agrocybe aegerita, Coprinellus radians and Marasmius rotula have demonstrated that APOs catalyze numerous H2O2-dependent monooxygenations of pharmaceuticals and psychoactive drugs. Among them are i) the monooxygenation of aromatic compounds, ii) the benzylic hydroxylation of toluene derivatives, iii) the O-dealkylation of different ether structures including the scission of benzodioxoles (O-demethylenation) and esters as well as iv) the N-dealkylation of secondary and tertiary amines. The peroxygenases studied considerably differ in their substrate spectrum and the preferred positions of oxidation. This finding opens the possibility to develop in the future an “enzymatic toolbox“ on the basis of fungal peroxygenases for the oxyfunctionalization of pharmaceutically relevant compounds. Mechanistic studies showed that (1) the monooxygenations always proceed via incorporation of one oxygen atom from the peroxide, (2) the demethylation of phenacetind1 established a deuterium isotope effect similar to P450s, (3) the catalytic efficiencies for the studied oxidations are in the same range as those of P450s (though the kcat- and Km values are noticeably higher), (4) the kinetic studies with nitro-1,3-benzodioxole gave parallel double reciprocal plots suggestive of a “ping pong” mechanism, (5) the substrate spectrum and the activity pattern of APOs follows in a wide range those of the human key P450s as well as that (6) the difference spectra obtained in bindings studies are of the phenol type of P450s. Furthermore, APOs were found to be stable and active in long term experiments over two weeks and they oxidized pharmaceuticals at low, environmentally relevant concentration (ppb range). All the above properties strongly indicate that APOs respresent an interesting alternative for the enzymatic conversion of pharmaceuticals as well as for the preparation of human drug metabolites, for example, in medicinal and pharmacological research or the bioremediation sector (removal of pharmaceuticals from environmental media).
In den letzten Jahren sind Pharmazeutika und deren Metabolite mehr und mehr in den Fokus der Wissenschaft gerückt. Diese Substanzen sind aufgrund ihrer physiologischen und toxikologischen sowie ökotoxikologischen Wirkungen im menschlichen Körper bzw. in der Umwelt von besonderem Interesse. Cytochrom-P450-Enzyme (P450s) spielen eine Schlüsselrolle bei der Umsetzung und Detoxifizierung bioaktiver Substanzen, darunter vieler Pharmazeutika und Drogen. Es handelt sich bei diesen Enzymen in erster Linie um Monooxygenasen, die intrazellulär lokalisiert und relativ instabil sind; sie benötigen komplexe, teure Kofaktoren und sind nur unter hohem Aufwand zu reinigen, was ihre Anwendung in isolierter Form insgesamt erschwert. Die hier durchgeführten Untersuchungen zu pilzlichen Peroxygenasen haben gezeigt, dass diese Enzymsubklasse (EC 1.11.2.x) ein hohes Oxyfunktionalisierungspotenzial besitzt und eine Vielzahl P450-typischer Reaktionen zu katalysieren vermag. Peroxygenasen sind extrazelluläre, d.h. sekretierte Pilzenzyme, die eine hohe Stabilität aufweisen und lediglich ein Peroxid als Kosubstrat benötigen. Die unter Verwendung der unspezifischen/aromatischen Peroxygenasen (APOs) von Agrocybe aegerita, Coprinellus radians und Marasmius rotula gewonnenen Ergebnisse belegen, dass APOs verschiedene H2O2-abhängige Monooxygenierungen von Pharmazeutika und psychoaktiven Substanzen realisieren. Dazu gehören i) die Monooxygenierung von Aromaten, ii) die benzylische Hydroxylierung von Toluolderivaten, iii) die O-Dealkylierung verschiedener Etherstrukturen einschließlich der Spaltung von Benzodioxolen (O-Demethylenierung) und Estern sowie iv) die N-Dealkylierung von sekundären und tertiären Aminen. Die untersuchten Peroxygenasen wiesen teilweise deutliche Unterschiede im Substratspektrum und den präferierten Oxidationspositionen auf. Dieser Befund eröffnet die Möglichkeit, zukünftig einen „enzymatischen Werkzeugkasten“ auf Basis pilzlicher Peroxygenasen für die Oxyfunktionalisierung von pharmazeutisch relevanten Wirkstoffen zu entwickeln. Mechanistische Experimente zeigten, dass (1) die Monooxygenierungen stets unter Einbau eines aus dem Peroxid stammenden Sauerstoffatoms erfolgen, (2) die Deethylierung von Phenacetin-d1 einen Deuteriumisotopeneffekt ähnlich dem der P450s aufweist, (3) die katalytischen Effizienzen für die untersuchten Oxidationen im gleichen Bereich wie die der P450s liegen (wobei die kcat- und Km-Werte deutlich höher ausfallen), (4) die kinetischen Untersuchungen zur Oxidation von Nitro-1,3-Benzodioxol parallele Verläufe der ermittelten Ausgleichsgeraden in der doppelt reziproken Darstellung ergaben, was für einen “Ping-Pong-Mechanismus“ spricht, (5) sich das Substratspektrum und die Aktivitätsmuster der APOs in einem weiten Bereich mit denen der wichtigsten menschlichen P450s decken sowie dass (6) die in Bindungsstudien gewonnenen Differenzspektren denen des Phenoltyps der P450s entsprechen. Desweiteren erwiesen sich APOs in Langzeitexperimenten über zwei Wochen als stabil und aktiv und sie waren in der Lage, Pharmazeutika in umweltrelevanten Konzentrationen (ppb-Bereich) zu oxidieren. All die genannten Eigenschaften legen nahe, dass APOs eine interessante Alternative zur enzymatischen Umsetzung von Pharmazeutika sowie zur Herstellung von humanen Pharmazeutika-Metaboliten darstellen, die z.B. Einsatz in der medizinischpharmakologischen Forschung oder im Umweltbereich (Entfernung von Pharmazeutika aus Umweltmedien) finden könnten.

Parkinson’s disease is an age-related neurodegenerative disorder. The major symptoms of Parkinson’s disease are closely linked to the pathology of the disease. The main pathology of Parkinson’s disease consists of the degeneration of neurons of the substantia nigra pars compacta (SNpc), which leads to reduced amounts of dopamine in the brain. One of the treatment strategies in Parkinson’s disease is to conserve dopamine by inhibiting the enzymes responsible for its catabolism. The monoamine oxidase (MAO) B isoform catalyses the oxidation of dopamine in the central nervous system and is therefore an important target for Parkinson’s disease treatment. Inhibition of MAO-B provides symptomatic relief for Parkinson’s disease patients by increasing endogenous dopamine levels as well as enhancing the levels of dopamine after administration of levodopa (L-dopa), the metabolic precursor of dopamine. Recent studies have shown that phthalide can be used as a scaffold for the design of reversible MAO inhibitors. Although phthalide is a weak MAO-B inhibitor, substitution on the C5 position of phthalide yields highly potent reversible MAO-B inhibitors. In the present study, sesamol and benzodioxane were used as scaffolds for the design of MAO inhibitors. The structures of sesamol and benzodioxane closely resemble that of phthalide, which suggests that these moieties may be useful for the design of MAO inhibitors. This study may be viewed as an exploratory study to discover new scaffolds for MAO inhibition. Since substitution at C5 of phthalide with a benzyloxy side chain yielded particularly potent MAO inhibitors, the sesamol and benzodioxane derivatives possessed the benzyloxy substituent in the analogous positions to C5 of phthalide. These were the C5 and C6 positions of sesamol and benzodioxane, respectively. The sesamol and benzodioxane derivatives were synthesised by reacting sesamol and 6- hydroxy-1,4-benzodioxane, respectively, with an appropriate alkyl bromide in the presence of potassium carbonate (K2CO3) in N,N-dimethylformamide (DMF). 6-Hydroxy-1,4- benzodioxane, in turn, was synthesised from 1,4-benzodioxan-6-carboxaldehyde. The structures of the compounds were verified with nuclear magnetic resonance (NMR) and mass spectrometry (MS) analyses, while the purities were estimated by high-pressure liquid chromatography (HPLC). Sixteen sesamol and benzodioxane derivatives were synthesised. To determine the inhibition potencies of the synthesised compounds the recombinant human MAO-A and MAO-B enzymes were used. The inhibition potencies were expressed as the corresponding IC50 values. The results showed that the sesamol and benzodioxane derivatives are highly potent and selective inhibitors of MAO-B and to a lesser extent MAOA. The most potent MAO-B inhibitor was 6-(3-bromobenzyloxy)-1,4-benzodioxane with an IC50 value of 0.045 μM. All compounds examined displayed selectivity for the MAO-B isoform over MAO-A. Generally the benzodioxane derivatives were found to be more potent inhibitors of human MAO-A and MAO-B than the sesamol derivatives. The reversibility and mode of MAO-B inhibition of a representative derivative, 6-(3- bromobenzyloxy)-1,4-benzodioxane, was examined by measuring the degree to which the enzyme activity recovers after dialysis of enzyme-inhibitor complexes, while Lineweaver- Burk plots were constructed to determine whether the mode of inhibition is competitive. Since MAO-B activity is completely recovered after dialysis of enzyme-inhibitor mixtures, it was concluded that 6-(3-bromobenzyloxy)-1,4-benzodioxane binds reversibly to the MAO-B enzyme. The Lineweaver-Burk plots constructed were linear and intersected on the y-axis. Therefore it may be concluded that 6-(3-bromobenzyloxy)-1,4-benzodioxane is a competitive MAO-B inhibitor. To conclude, the C6-substituted benzodioxane derivatives are potent, selective, reversible and competitive inhibitors of human MAO-B. These compounds are therefore promising leads for the future development of therapy for Parkinson’s disease.
MSc (Pharmaceutical Chemistry), North-West University, Potchefstroom Campus, 2015