Quinazolines

A method was developed for the preparation of 2,3-polymethylene-3,4-dihydro-4-quinazolones with substituents in the benzene and polymethylene chains by reaction of anthranilic acid and its substituted derivatives with -butyro-, 5-phenyl--butyro-, -capro-, and -chloro--caprolactams in the presence of dehydrating agents. The corresponding quinazolines were obtained by reduction of the synthesized quinazolones.See [1] for communication V.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1564–1569, November, 1976.     

Quinazolines and 1,4-benzodiazepines. LXXIII. The ring expansion of 2-chloromethylquinazoline 3-oxides with nitromethane

The reaction of 2-chloromethylquinazoline 3-oxides (3) with the anion of nitromethane gave the 2-nitromethylene benzodiazepine oxides (4) as a result of ring expansion. Other nucleophiles led only to products derived from substitution of the halogen. The ring expansion of 2,2-dichloro-1,2-dihydroquinazolines with nitromethane anion is also described.     

Quinazolines and 1,4-benzodiazepines LXVIII. 5-Heterocyclic-substituted benzodiazepinones

The synthesis of a number of new 1,4-benzodiazepin-2-ones containg the 2-thiazolyl, 5-isothiazolyl, 1-rnethyl-2-imidazolyl. 1-methyl-5-pyrazolyl, and 3,5-dimethyl-4-isoxazolyl groups in the 5-position of the benzodiazepine ring are described.     

Quinazolines and 1,4-benzodiazepines LVII. 1H-1,4-benzodiazepines

The preparation of the title compounds 3 and 4 using two different methods of synthesis is described. These compounds are readily reduced to 2,3-dihydro-1H-derivatives 5 . Oxidation of 2-alkylthio-1H-1,4-benzodiazepines leads to the corresponding sulfoxides and sulfones. The oxidative rearrangement of sulfones 9 to a 2H-1,4-benzodiazepin-2-one derivative 10 is also given. The “normal” addition of azodicarboxylate together with an unusual addition of two moles of acetylenedicarboxylate to the enamine double bond of 1H compounds is discussed.     

Quinazolines XI. Condensation of deoxyvasicinone with aldehydes

Summary In the reaction of deoxyvasicinone with aldehydes, depending on the nature of the substituents of aromatic and heterocyclic aldehydes, and also on the reaction conditions, 9-benzylidene or 9--hydroxybenzyl derivatives of deoxyvasicinone are obtained.Institute of the Chemistry of Plant Substances, Academy of Science of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 552–556, July–August, 1977.     

Quinazolines and 1,4-benzodiazepines. XLVI. Photochemistry of nitrones and oxaziridines

The cyclic nitrones 7-chloro-1,3-dihydro-5-phenyl-2H-1,4-benzodiazepin-2-one 4-oxide ( 5a ) and 1,3-dihydro-7-methylthio-5-phenyl-2H-1,4-benzodiazepin-2-one 4-oxide ( 5b ) are photoisomerized to readily isolable oxaziridines, 7-chloro-4,5-epoxy-5-phenyl-1,3,4–5-tetrahydro-2H-1,4-benzodiazepin-2-one ( 6a ) and 4,5-epoxy-5-phenyl-1,3,4,5-tetrahydro-7-methylthio-2H-1,4-benzo-diazepin-2-one ( 6b ). Oxaziridine 6b upon further irradiation gave ring expansion and ring contraction products, 4,6-dihydro-2-phenyl-9-methylthio-5H-1,3,6-benzoxadiazocin-5-one ( 7b ) and 4-benzoyl-3,4-dihydro-6-methylthioquinoxalin-2(1H)-one ( 8b ) respectively. The ring contraction product, 4-benzoyl-6-chloro-3,4-dihydroquinoxalin-2(1H)-one ( 8a ), was obtained from irradiation of oxaziridine 6a .     

Quinazolines X. Synthesis of 6,6'-methylenebisdeoxyvasicinone and its homologs

Summary 6,6-Methylenebisdeoxyvacisinone and its homologs have been synthesized by the reaction of methylenebisanthranilic acid with lactams (-butyrolactam, -valerolactam, -caprolactam, and -chloro- and ,-dichloro--caprolactams). The condensation of anthranilic acid and its derivatives (4-nitro-, 5-bromo-, 5-iodo-, and 5-nitroanthranilic acids) with ,-dichloro--caprolactam has given seven-membered analogs of deoxyvasicinone containing two chlorine atoms in the polymethylene ring.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 544–547, July–August, 1977.     

Quinazolines and 1,4-benzodiazepines. LXI. Syntheses of 7-Acetyl-1,4-benzodiazepines

Methods for the synthesis of the biologically active 7-acetyl-1,3-dihydro-5-phenyl-2H-1,4-benzodiazepin-2-one ( 6 ) are described. This includes two new methods for the preparation of 5-acetyl-2-aminobenzophenone ( 4 ). The crucial steps in these syntheses involve, respectively, the oxidation of an ethyl group to an acetyl group with permanganate or ceric ions ( 2 → 3; 5 → 6 ), the selective reaction of methyl lithium with the cyano group of 7-cyano-1,3-dihydro-5-phenyl-2H-1,4-benzodiazepin-2-one ( 8 ) and the efficient condensation of benzyl cyanide with the ethylene ketal of p-nitroacetophenone to form the anthranil 11 .     

Quinazolines and 1,4-benzodiazepines. LXXXV syntheses of 3-substituted lmidazo[1,5-a] [1,4]benzodiazepines

1,4-Benzodiazepines having a leaving group in the 2-position were condensed with carbanions of 1,3-dicarbonyl compounds. The products obtained were converted to the title compounds by a sequence of steps involving hydrolytic decarboxylation, nitrosation, catalytic hydrogenation and condensation with an orthoester or an amide acetal. Oxidative condensation of the enediamine 12 with a variety of aldehydes also led to imidazo-benzodiazepines with various substituents in the 1-position.     

Quinazolines 1. Synthesis and chemical reactions of 6-chlorosulfonyl-quinazoline-2,4-diones

Treatment of quinazoline-2,4-dione and its symmetrical 1,3-dialkyl derivatives with chlorosulfonic acid gave the corresponding 6-chlorosulfonylquinazoline-2,4-diones. Reaction of the compounds obtained with nucleophilic agents (water, ammonia, aliphatic and cyclic amines) gave the corresponding free 2,4-dioxoquinazoline-6-sulfonic acids, 6-sulfamidoquinazoline-2,4-diones, and 2,4-dioxoquinazoline-6-sulfonic acid amides. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 420–427, March 2008.     

Quinazolines and 1,4-benzodiazepines. LXXXVII. Synthesis of 1- and 3-phenylimidazo[1,5-a] [1,4]benzodiazepines

The synthesis of the 1-phenylimidazobenzodiazepine 5 from 1 and the anion of the nitrone 2 is described. The 3-phenyl-derivative 14 was prepared via the ammo alcohol 11 which was obtained by condensation of the nitrosamine 9 with benzaldehyde followed by catalytic hydro-genolysis of the nitroso group.