A facile synthesis of novel pyrazolo[5′,1′:3, 4]-[1, 2, 4]triazino[6, 5-f][1, 3, 4]thiadiazepines

The reaction of the 3-substituted 4-aminopyrazolo[5, 1-c][1, 2, 4]triazines 1a-d with thiosemicarbazide hydrochloride in acetic acid gave new pyrazolo[5′,1′:3, 4][1, 2, 4]triazino[6, 5-f][1, 3, 4]thiadiazepines 3, 4 and 6 , which were converted into the 5-oxo derivatives 5 and 7 by hydrolysis in hydrochloric acid/acetic acid.     

Anthra[1,2-b]furan and 1h-naphth[2, 3-g]indole derivatives

A number of previously inaccessible anthra[1,2-b]furan and 1H-naphth[2,3-g]indole derivatives were obtained by condensation of 1,4-anthraquinone with acetoacetic ester and its analogs. Quinones of the anthra[1,2-b]furan series were obtained by oxidation of the methoxy derivatives of anthra[1,2-b]furan.Translated from Khimiya Geterotsiklicheskikh Soedtaenii, No. 8, pp. 1027–1029, August, 1972.     

Synthesis and 13C-NMR study of novel pyrazolo[5′,1′:3, 4][1, 2, 4]triazino[5, 6-d]pyrimidines

The pyrazolo[5′, 1′:3, 4][1, 2, 4]triazino[5, 6-d]pyrimidines 5a-c, 6 were synthesized from the pyrazolo[5, 1-c]-[1, 2, 4]triazines 1a, c and the ring carbon signals of 5a-c, 6 were assigned by the aid of coupling constant [J( 13 C-¹H)] data.     

Synthesis of 2-R-3-Hydroxy[1,2,4]triazino[6,1-b]-quinazoline-4,10-diones

A preparation method was developed for [1,2,4]triazino[6,1-b]quinazoline-4,10-diones using isatoic anhydride, carboxylic acids hydrazides, ethyl oxalyl chloride, and hydroxylamine.     

Synthesis of Some New 3-Alkylthio Derivatives of 1-Phenyl-1H-[1, 3, 4]thiadiazino[5, 6-b]quinoxalines

The synthesis of some new 3-(alkylthio)-1-phenyl-1H-[1, 3, 4]thiadiazino[5, 6-b]quinoxalines 4 have been achieved by cyclocondensation reaction of the alkyl-2-phenylhydrazinecarbodithioates 1 with 2,3-dichloroquinoxaline 2 in basic N,N-dimethylformamide.     

The synthesis of 4-benzylamino-6-methyl-1H-pyrrolo[3, 2-c]pyridine and 4-benzylamino-6-methyl-1H-pyrrolo[2, 3-b]pyridine

4-Benzylamino-6-methyl-1H-pyrrolo[3,2-c]pyridine ( 2 ) and 4-benzylamino-6-methyl-1H-pyrrolo[2,3-b]pyridine ( 3 ) were synthesized as deaza analogues of the anxiolytic agent 4-benzylamino-2-methyl-7H-pyrrolo[2,3-d]pyrimidine ( 1 ). The 1-deaza analogue (2) was prepared via a multi-step procedure from a pyrrole precursor, 1-benzyl-2-formylpyrrole ( 4 ) while the 3-deaza analogue 3 was synthesized from a pyridine precursor, 2-amino-3,6-dimethylpyridine ( 12 ).     

Facile synthesis of [1,2,4]triazino[4,3-b][1,2,4,5]tetrazepin derivatives by a one-pot reactions using 4-amino-3-hydrazinyl-6-methyl-1,2,4-triazin-5 (4H)-one

<正>4-Amino-3-mercapto-6-methyl-l,2,4-triazin-5(4H)-one 1 converted to 4-amino-6-methy-3-(methylthio)-1,2,4-triazin-5(4H)-one by methylation with methyl iodide.Controlled hydrazination of the resulting compound afforded 4-amino-3-hydrazinyl-6- methyl-l,2,4-triazin-5(4H)-one 2 as a building block,to the synthesis of some novel derivatives of[1,2,4]triazino- [4,3,b][1,2,4,5]tetrazepine 3-6,by the reaction with 3-chloropentane-2,4-dione,chloro acetonitrile,1,3-dichloroacetone,and methyl bromoacetate.This general synthetic procedure can be extended to the preparation of wide variety of tetrazepines using 1,2- bielectrophiles derivatives.     

A Facile Synthesis of Novel 9-Methyl[1, 2, 3]Selenadiazoles[4, 5-b]Quinoline and 9-Methyl[1, 2, 3]Thiadiazole[4, 5-b]Quinoline as a New Class of Antimicrobial Agents

2-chloro-4-methyl quinoline 2 on condensation with semicarbazide hydrochloride gave its semicarbazone. This on reaction with SeO ₂ and SOCl₂ yielded a new class of novel selenadiazoles 4 and thiadiazoles 5, respectively. The structure of all the compounds were elucidated on the basis of elemental analysis, IR, ¹ H NMR, and the mass spectral data. Some derivatives of 9-methyl[1, 2, 3]selenadiazole[4, 5-b] quinoline and 9-methyl[1, 2, 3]thiadiazole [4, 5-b]quinoline have been screened for antimicrobial activities.     

[1,2,4]Triazines. 4. Regiospecific ring closure reactions involving 6-amino-5-hydrazino[1,2,4]triazin-3(2H)-ones and orthoesters

6-Amino-5-hydrazino[1,2,4]triazin-3(2H)-one, 3 , was treated with a variety of orthoesters and concentrated acid forming mixtures of ring-closed and open-chain derivatives. These mixtures were converted in warm aqueous acid to the Mriazolo[5,1-d][1,2,4]triazin-3(2H)-ones, 11b, 14b , and 15b by a regiospecific ring closure at N-4 of the [1,2,4]triazine ring and subsequent Dimroth-like rearrangement of the initially formed s-triazolo[4,3-d][1,2,4]triazin-3(2H)-ones ( 11a, 14a, 15a ).     

Synthesis of 3H[1,2]diazepino[5,6-b]indole and 3H[1,2]diazepino[4,5-b]indole derivatives

The synthesis of two new derivatives of 3H[1,2]diazepino[5,6-b]indole, 5 and 11 , and one new derivative of 3H[1,2]diazepino[4,5-b]indole, 16 , are described. Compound 5 was obtained by the reaction of methyl 2-(3-methoxycarbonyl-1-methylindole)acetate 2 , with hydrazine. Compound 11 was obtained in two ways from ethyl 2-(1-methylindole)acetate ( 8 ) by formylation and reaction with hydrazine. Compound 16 was obtained treating 3-(2-ethoxycarbonylindole)acetonitrile ( 14 ) with hydrazine.     

3, 6-二取代-均三唑并[3, 4-b]-1, 3, 4-噻二唑的合成

研究了2-苯基-1, 2, 3-三唑-4-羧酸(1)与3-烷基/芳基-4-氨基-5-巯基-1, 2, 4-三唑(2a～o)在POCl~3催化下, 脱水缩合得到15个新的3-烷基/芳基-6-(2'-苯基-1', 2', 3'-三唑-4'-基)均三唑并[3,4-b]-1, 3, 4-噻二唑类化合物(3a～o)。     

Some chemical properties and reactions of 3-phenylimidazo[5, 1-b]benzoxazole

It has been shown that 3-phenylimidazo[5, 1-b]benzoxazole (I) is stable under conditions of alkaline and acid hydrolysis. When I is oxidized with potassium permanganate, 2-benzoylbenzoxazole is formed. A series of 1-substituted derivatives of I has been obtained by its nitration and bromination and by the Vilsmeier and Mannich reactions. Nitrosation, hydroxymethylation, acetylation, and cyanoethylation reactions of I could not be carried out by the usual methods.     

6-Amino-5-cyano-1H,4H-pyrazolo[3,4-b]pyrans

The reaction of 3-methyl-1-phenyl-5-pyrazolene with arylideneamino nitriles in alcohol leads to the formation of 3-methyl-4(1-aryl-2,2-dicyanoethyl)-5-pyrazolones, which are readily cyclized in the presence of bases to the corresponding 6-amino-5-cyano-3-methyl-4-aryl- 1H,4H-pyrazolo[3,4-b]pyrans. The structures of the intermediate and final products were confirmed by the IR, UV, PMR, and mass spectra.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 801–806, June, 1982.     

5α-androstano [3,2-b]pyridines, 5α-androstano[17,16-b]pyridines and androst-4 and 5-eno[17,16-b]pyridines

A new synthesis of 5α-androstano[3,2-b]pyridin-17β-ol acetate (VIa) and 17-methyl-5α-androstano[3,2-b]pyridin-17β-ol (VIb), first reported by Shimizu, Ohta, Ueno, and Takegoshi, was achieved. The analogous 5α - androstano[17,16-b]pyridin-3β-ol (XII), 5α-androstano[17,16-b]pyridin-3-one (XIVa), and androst-4-eno[17,16-b]pyridin-3-one (XIVb) were also prepared. An illustration of the method follows. Condensation of 3β-hydroxy-5α-androstan-17-one (VIIa) with 3-(2-furyl)acrolein afforded 16-[3-(2-furyl)-2-propenylidene]-3β-hydroxy-5α-androstan-17-one (VIIIa), the oxime (IXa) of which was thermally cyclized to 5α-androstano[17,16-b]-6′-(2-furyl)pyridin-3β-ol (Xa). 3β-Hydroxy-5α-androstano[17,16-b]pyridine-6′-carboxylic acid (XI) was obtained by ozonolysis of Xa. Thermal decarboxylation of XI gave XII. Cinnamaldehyde was used in place of 3-(2-furyl)acrolein to give the corresponding phenylpyridines.     

3, 6-二芳基-5, 6-二氢均三唑[3, 4-b][1, 3, 4]噻二唑的合成 及生物活性

研究了在L-(+)-酒石酸存在下3-芳基-4-氨基-5-巯基-1,2,4-均三唑与醛的Mannich反应及分子内的加成反应,合成了15个新的手性稠杂环化合物3,6-二芳基-5,6-二氢均三唑[3,4-b][1,3,4]噻二唑,利用IR、^1HNMR和MS确证了其结构,并测试了部分化合物的生物活性。     

Unexpected hydrazinolysis behaviour of 1-chloro-4-methyl-5H-pyridazino[4,5-b]indole and a convenient synthesis of new [1,2,4]-triazolo[4',3':1,6]pyridazino[4,5-b]indoles

Reaction of the title compound with hydrazine in the presence of air gives the 1-unsubstituted parent system via oxidative dehydrazination of the 1-hydrazino intermediate. The latter can be obtained in high yield by carrying out the hydrazinolysis step under inert gas, and it is smoothly converted into [1,2,4]-triazolo[4',3':1,6]pyridazino[4,5- b]indoles.