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Alprazolam underwent a facile 1,4-benzodiazepine ring-opening reaction in an acidic aqueous solution to form a benzophenone compound. The reaction was demonstrated by means of UV, IR, and 1H- and 13C-NMR spectroscopy. Its reverse cyclization reaction to alprazolam occurred when an acidic solution was neutralized. Both the ring-opening and the cyclization rate constants were obtained from the overall rate constant measured at 25° over a pH range of 0.5-8.0; the latter was measured by monitoring the UV spectral change of the reaction. Although the equilibrium was favored for the benzophenone compound in acidic solutions, it was possible to directly measure the cyclization rate at three acidic pH values by providing a sink condition for the product, alprazolam, using a biphasic reaction system. The bell-shaped cyclization rate pH profile was interpreted in terms of a change in the rate-determining step. The pH profile of the ring-opening rate showed an inflection point indicating a different reactivity of mono- and dicationic alprazolam. The apparent equilibrium between alprazolam and the benzophenone compound at a given pH was estimated from the rate constants for the ring-opening and cyclization reactions. The results agree with the apparent pK(α) measured by a conventional UV spectrophotometry and a titration technique. The pK(α) of monocationic alprazolam, the reactive species for the covalent hydration, was determined from the pH dependence of the initial absorbance when an alprazolam solution is acidified.

A reagent-free intramolecular dehydrogenative C-N cross-coupling reaction has been developed under mild electrolytic conditions. In this atom- and step-economical one-pot process, valuable 1,2,4-triazolo[4,3-a]pyridines and related heterocyclic compounds could be synthesized efficiently from commercially available aliphatic or (hetero)aromatic aldehydes and 2-hydrazinopyridines. Various functional groups are compatible with this metal- and oxidant-free protocol which can be carried out on a gram scale easily. This novel method was applied to the synthesis of one of the top-selling drugs Xanax and late stage functionalization for generating chemical diversity in biologically relevant lead molecules.

A new method for the synthesis of 8-chloro-1-methyl-6-phenyl-4H-benzo[f][1,2,4]triazolo[4,3-a][1,4]diazepine (alprazolam) and 7-chloro-1-methyl-5-phenyl-1H-benzo[e][1,4]diazepin-2(3H)-one (diazepam) from 2-amino-5-chloro benzophenone was described under mild conditions. Most of the synthetic steps were carried out under solvent-free conditions, and the products were obtained in high yield and purity. The products were characterized by comparison of physical properties with authentic samples and also by IR, 1H NMR and 13C NMR. Three-dimensional (3D) model of GABAA was constructed using X-ray crystal structure of homopentameric caenorhabditis elegans glutamate-gated chloride channel (GluCl) (3RHW) at 3.3?? as the template based on sequence comparison and homology modeling method. The homology modeling and MD simulation studies predicted the 3D structure of receptor in a water environment. The resulted conformation of the receptor was used for docking of the alprazolam and diazepam. Docking studies indicated many important interactions of the drugs with the receptor. Furthermore, the complex of GABA with drugs was used in MD simulation to realize the conformation changes of the complex.

An improved process for preparation of triazol-benzodiazepine derivatives, such as alprazolam, triazolam, brotizolam and etizolam, is presented. The process comprises a cyclization reaction of compound Formula B in toluene with catalytic amount of p-toluene sulphonic acid to obtain the triazol-benzodiazepine derivative of Formula C: wherein R is, and X is hydrogen or halogen.

An improved process for preparation of triazol-benzodiazepine derivatives, such as alprazolam, triazolam, brotizolam and etizolam, is presented. The process comprises a cyclization reaction of compound Formula B in toluene with catalytic amount of p-toluene sulphonic acid to obtain the triazol-benzodiazepine derivative of Formula C: wherein R is, and X is hydrogen or halogen.

1,4-Benzodiazepine N-nitrosoamidines have been used as scaffolds for the preparation of different tricyclic derivatives. Replacement of the N-nitrosoamidine moiety through treatment with the nucleophiles acetylhydrazine, aminoacetaldehyde dimethylacetal and 1-amino-2-propanol, followed by an acid-catalyzed cyclization step, afforded triazolo and imidazobenzodiazepines 1, 6, and 7, respectively, in good yields. When acetylhydrazine is used as a nucleophile, the overall process provides an alternative route to alprazolam (1b) and triazolam (1c), respectively.

A pharmaceutical composition an inclusion complex and methods for treating patients and preparing said complex disclosed for transmucosal delivery comprising an inclusion complex of (a) alprazolam and (b) a water soluble 2-hydroxypropyl-beta-cyclodextrin, and a pharmaceutically acceptable carrier therefor, wherein all the alprazolam is present in ring-closed form.

Methods for enhancing the complexation efficiency of a drug with cyclodextrin and for enhancing the availability of a drug following administration of a cyclodextrin-drug complex.

Neuroprotective agents are disclosed having the following structure: wherein R1, R2, R3, R4and R5are as defined herein. Such compounds have utility in the treatment of conditions which benefit from administration of neuroprotective agents generally, including treatment of central and peripheral nervous condition as well as for promoting nerve cell differentiation. Methods of treating such conditions are also disclosed, as are pharmaceutical compositions containing one or more of the compounds of this invention.

Methods and compositions are disclosed employing combinations of antihistamines with certain diaryl tetrahydrofuran, diaryl tetrahydrothiophene, triazolobenzodiazepine or thienotriazolodiazepine PAF--antagonist compounds in the treatment of allergic reactions.

Compounds of the general formula STR1 are reacted with a strong base followed by a phosphorylating agent, such as dicyclicaminophosphinic halide or bis-di-lower alkylaminophosphinic halide to produce an imine of the formula STR2 wherein R is dicyclicaminophosphinyloxy or bis-di-lower alkylaminophosphinyloxy. R represents a leaving group which will undergo nucleophilic displacement with nitrogen, oxygen, sulfur and carbon containing nucleophiles, that is, nucleophiles which have, as a reactive site, a nitrogen, oxygen, sulfur or carbon atom, such that, when the cyclic imine undergoes nucleophilic displacement, there is formed C--N, C--O, C--S and C--C bonds between the carbon atom of the cyclic imine and the nucleophilic group. The end products may be utilized as intermediates in the production of pharmaceutically valuable compounds and, in some instances, are pharmaceutically valuable compounds per se.

Several 6-phenyl-4H-s-triazolo[4,3-α][1,4]benzodiazepines have useful biological activity both in experimental animals and in man. This manuscript describes a novel synthesis of these compounds from intermediates that do not have a pre-formed benzodiazepine ring system.

Benzodiazepine derivatives of the general formula STR1 where R1 is hydrogen or a hydrocarbon residue of 1-8 carbon atoms, R2 is hydrogen or lower alkyl and rings A and B are unsubstituted or substituted by nitro, trifluoromethyl, halogen, lower alkyl or lower alkoxy, the nitrogen atom in the 5-position being unsubstituted or substituted by an oxygen atom, useful as muscle relaxants, anticonvulsants, sedatives and tranquilizing agents, and processes for production thereof. Also provided are novel intermediates of the general formula STR2 where R2 has the above meaning, rings A and B are unsubstituted or substituted as above and the nitrogen atom in the 4-position is unsubstituted or substituted by an oxygen atom.

The title compounds are prepared by reacting a 3-amino-3,4-dihydro-4-hydroxy-4-phenylquinazoline with a reactive derivative of a halogenoacetic acid, reacting the resultant halogenoacetyl derivative with a weak acid, reacting the resultant 2-(3-halomethyl-s-triazol-4-yl)benzophenone with hydroxylamine and subjecting the resultant 2-(3-hydroxyamino-methyl-s-triazol-4-yl)benzophenone to dehydration to effect ring closure.

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A process to make 6-phenyl-4H-s-triazolo[4,3-a][1,4]-benzodiazepines by converting 2-[3-(hydroxymethyl)-4H-1,2,4-triazol-4-yl]benzophenones to 2-[3-[(phthalimido or methanesulfonyl)methyl]-4H-1,2,4-triazol-4-yl]benzophenones and converting these compounds to the highly active 6-phenyl-4H-s-triazolo[4,3-a][1,4]benzodiazepines useful as tranquilizers and sedatives.

6-Phenyl-4H-s-triazolo[4,3-a][1,4]benzodiazepines of the formula (IV): SPC1 wherein R is selected from the group consisting of hydrogen, alkyl of 1 to 3 carbon atoms, inclusive, phenyl, benzyl and -COOR' in which R' is alkyl of 1 to 4 carbon atoms, inclusive; wherein R1 is selected from the group consisting of hydrogen and alkyl of 1 to 3 carbon atoms, inclusive; and wherein R2, R3, R4 and R5 are selected from the group consisting of hydrogen, alkyl of 1 to 3 carbon atoms, inclusive, halogen, nitro, cyano, trifluoromethyl, and alkoxy, alkylthio, alkylsulfinyl, alkylsulfonyl, alkanoylamino and dialkylamino in which the carbon chain moieties are of 1 to 3 carbon atoms, inclusive, are produced by condensing a 1,3-dihydro-5-phenyl-2H-1,4-benzodiazepine-2-thione of the formula (I): SPC2 wherein R1, R2, R3, R4 and R5 are defined as above, with an organic acid hydrazide of the formula: EQU1 wherein R is defined as above. The new products of formula IV including their pharmacologically acceptable acid addition salts are useful as sedatives, tranquilizers and muscle relaxants in mammals and birds.

Intermediates of the formula IV: STR1 wherein R is selected from the group consisting of hydrogen and alkyl of 1 to 3 carbon atoms, inclusive; and wherein R2, R3, and R4 are selected from the group consisting of hydrogen, fluoro, chloro, bromo, nitro, and trifluoromethyl are produced by a multistep synthesis. The final compounds are tranquilizers and sedatives and can be used in mammals, including man, and in birds.

An animal feed comprising a compound of the group consisting of 6-phenyl-4H-s-triazolo[4,3-a][1,4]benzodiazepines of the formula: STR1 WHEREIN R is selected from the group consisting of hydrogen, alkyl of 1 to 3 carbon atoms, inclusive, phenyl, benzyl and -COOR' in which R' is alkyl of 1 to 4 carbon atoms, inclusive; wherein R1 is selected from the group consisting of hydrogen and alkyl of 1 to 3 carbon atoms, inclusive; and wherein R2, R3, R4 and R5 are selected from the group consisting of hydrogen, alkyl of 1 to 3 carbon atoms, inclusive, halogen, nitro, cyano, trifluoromethyl, and alkoxy, alkylthio, alkylsulfinyl, alkylsulfonyl, alkanoylamino and dialkylamino in which the carbon chain moieties are of 1 to 3 carbon atom, inclusive and their pharmacologically acceptable acid addition salts in combination with a nutrient feed. A process for obtaining increased productivity in meat producing, milk producing, and egg laying animals by feeding the aforementioned compounds in combination with nutrient feeds.

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