利用串联的氮杂Wittig反应方便合成3-[取代吡啶(噻唑)甲基]-1,2,3-三唑[4,5-d]嘧啶-7-酮及其除草活性

用串联的氮杂Wittig关环反应合成了一系列3-[取代吡啶(嘧啶)甲基]-1,2,3-三唑[4,5-d]嘧啶-7-酮.膦亚胺4和芳基异氰酸酯发生氮杂Wittig反应生成碳二亚胺5,继而在乙醇钠催化下与各种脂肪伯胺关环,以较好的收率得到目标产物7.初步生物活性测试结果表明:该系列部分化合物在100 mg/L的浓度下对双子叶植物油菜显示出较好的除草活性.     

Palladium-Catalyzed Allylic Coupling of 1,2,3-Triazolo[4,5-d]pyrimidines (8-Azapurines)

The palladium-catalyzed coupling of the sodium salt of 7-amino-1,2,3-triazolo[4,5-d]pyrimidine (8-azaadenine, 1) with allylic phosphates or carbonates resulted in mixtures of 2- and 3-substituted 1,2,3-triazolopyrimidines, which were separated by chromatography. 1-Substituted triazolopyrimidines were not isolated from these reactions. Regioselectivity (and stereoselectivity) was also observed for substitution of the allylic moiety when more than one isomer is possible from the reaction. The use of 5-amino-1,2,3-triazolo[4,5-d]pyrimidin-7-ones (8-azaguanine, 2), instead of 8-azaadenine, also resulted in mixtures. Alternate syntheses of the 3-allyl-1,2,3-triazolo[4,5-d]pyrimidines confirmed the structures of these compounds.     

Synthesis and antiallergy activity of [1,3,4]thiadiazolo[3,2-a]-1,2,3-triazolo[4,5-d]pyrimidin-9(3H)-one derivatives. II. 6-Alkyl- and 6-cycloalkylalkyl derivatives.

A series of 6-alkyl- or 6-(cycloalkylalkyl)-[1,3,4]thiadiazolo[3,2- a]-1,2,3-triazolo[4,5-d]pyrimidin-9(3H)-ones 1b--o was synthesized from the corresponding 1,3,4-thiadiazol-5-amines 3b--o and the antiallergic activities of the products were evaluated. Among the compounds 6-(2-cyclohexylethyl)- [1,3,4]thiadiazolo[3,2-a]-1,2,3-triazolo[4,5-d]pyrimidin-9(3H)-one 1h, whose X-ray crystallographic stereostructure is shown, was found to be a promising new antiallergic agent, which has low toxicity and dual activity as a leukotriene D4 receptor antagonist and as an orally active mast cell stabilizer.     

Synthesis and Crystal Structure of 3-Benzyl-5-cyclohexylamino-6-phenyl-3,6-dihydro-l,2,3-triazolo[4,5-d]pyrimidin-7-one

The title compound 3-benzyl-5-cyclohexylamino-6-phenyI-3,6-dihydro-1,2,3-triazolo[4,5-d]pyrimidin-7-one (C23H24N6O, Mr = 400.48) has been synthesized by means of tandem aza-Wittig reaction, and its crystal structure was determined by single-crystal X-ray diffraction. The crystal belongs to monoclinic, space group P21/n with a = 6.5550(6), b - 10.3711(10), c = 31.265(3)(A), β = 93.827(2)° ,V = 2120.8(4) (A)3, Z = 4, Dc = 1.254 g/cm3, S = 1.025, μ(MoKa) = 0.081 mm-1, F(000) = 848, R = 0.0576 and wR = 0.1368. X-ray analysis reveals that all ring atoms in the triazolopyrimidinone moiety are almost coplanar and the cyclohexyl ring adopts a chair conformation.     

Annulated 1,2,3-triazoles. 3. Synthesis of 1,2,3-triazolo[4,5-b][1,5]benzoxazepin-10(9H)-ones and 10-(4-substituted-1-piperazinyl)-1,2,3-triazolo[4,5-b][1,5]benzoxazepines

10-(4-Substituted-1-piperazinyl)-1,2,3-triazolo[4,5-b][1,5]benzoxazepines 11 were prepared in a three-step synthesis starting from easily available 5-chloro-1,2,3-triazole-4-carbonyl chlorides 7 by titanium tetrachloride catalyzed condensation of N-(substituted)piperazines with 1,2,3-triazolo[4,5-b][1,5]benzoxazepin-10(9H)-ones 10 formed by ring closure of the intermediate amides 9 . Although lactams 10 were obtained as the sole product of the cyclisation at 80°, the unexpected by-products 13 and 14 were formed in addition to 10c at 150° from 9c . The 4-methoxybenzyl group in 11j was easily removed by solvolyses in TFA. Compounds 11d-f and 11i were tested for psychotropic activity.     

Synthesis and antiallergy activity of [1,3,4]thiadiazolo[3,2-a]-1,2,3-triazolo[4,5-d]pyrimidin-9 (3H)-one derivatives. I.

A series of 6-substituted [1,3,4]thiadiazolo[3,2-a]-1,2,3-triazolo[4,5-d]pyrimidin-9(3H)-one derivatives 4a--z were synthesized from 5-substituted 1,3,4-thiadiazol-2-amines 5 by the following consecutive reactions: pyrimidine ring closure with bis(2,4,6-trichlorophenyl) malonate, nitration, chlorination, amination, hydrogenation and diazotization. The structure of 4 was confirmed by an alternate synthesis of 4, involving reaction of 5-substituted 2-azido-1,3,4-thiadiazole 13 with ethyl cyanoacetate, followed by the Dimroth rearrangement and ring closure. The antiallergic activities (anti-passive peritoneal anaphylaxis, anti-passive cutaneous anaphylaxis and anti-slow reacting substance of anaphylaxis activities) of the products were evaluated.     

An efficient route for synthesis of 2-alkylamino benzo[b]thieno[3,2-d]pyrimidin-4(3H)-one

The carbodiimide 2,obtained from the aza-Wittig reactions of iminophosphorane 1 with alkyl isocyanates,reacted with primary amino to give 2-alkylamino benzo[b]thieno[3,2-d]pyrimidin-4(3H)-ones 4 and 5.The formation mechanism of the title compounds has been investigated.     

Efficient Synthesis of 3,5,6,7-Tetrahydro-4H-cyclopenta[4,5] thieno[2,3-d]Pyrimidin-4-ones

The title compounds 3,5,6,7-tetrahydro-4H-cyclopenta[4,5]thieno[2,3-d]pyrimidin-4-ones（6） were synthesized by base catalytic reactions of secondary amines with carbodiimides 4, which were obtained from the aza-Wittig reaction of iminophosphoranes（3） with aromatic isocyanates.     

A facile one-pot synthesis of 6,7,8,9-tetrahydrobenzo[4,5]thieno[2,3-d]-1,2,4-triazolo[4,5-a]pyrimidin-5-ones

Abstract  

The reaction of 2-mercapto-6,7,8,9-tetrahydro-3H-benzo[4,5]thieno[2,3-d]pyrimidin-4-one or its 2-methylthio derivative with hydrazonoyl halides, in the presence of triethylamine, yielded 6,7,8,9-tetrahydrobenzo[4,5]thieno[2,3-d]-1,2,4-triazolo[4,5-a]pyrimidin-5-ones. The structure of the latter compounds was further confirmed by reaction of 2-mercapto-6,7,8,9-tetrahydro-3H-benzo[4,5]thieno[2,3-d]pyrimidin-4-one with the appropriate active chloromethylenes followed by coupling of the products with benzenediazonium chloride to afford the non-isolable azo-coupling products which converted, in situ, to 6,7,8,9-tetrahydrobenzo[4,5]thieno[2,3-d]-1,2,4-triazolo[4,5-a]pyrimidin-5-ones. The reaction mechanism was proposed and the products were screened for their biological activity. Some of the newly synthesized compounds had a moderate effect against some bacterial and fungal species.     

1,2,3-Triazolo[4,5-d]-1,2,4-triazolo[4,3-b]pyridazines

Some new 1,2,3-triazolo[4,5-d]-1,2,4-triazolo[4,3-b]pyridazines were prepared starting from the corresponding 1,2,3-triazolo[4,5-d]pyridazines via the formation of the 1,2,4-triazole ring, by condensation of an appropriate monocarbon fragment with the 4-hydrazino substituent and the nitrogen atom in the 5 position of the heterocycle. Condensation of 4-phenylhydrazino substituted derivatives with formic acid gave zwitterionic compounds.     

Ring Transformation of 7-Nitro-1-(4-nitrophenyl)-4,5-dihydro-1H-imidazo- and -[1,2,3]triazolo[4,5-c]pyridin-4-ones

Nitration of 1-phenyl-4,5-dihydroimidazo- and -1,2,3-triazolo[4,5-c]pyridin-4-ones initially occurs at the para position of the phenyl ring, and the subsequent nitration yields the corresponding 7-nitro-1-(4-nitrophenyl) derivatives. Treatment of the latter with hydrazine hydrate leads to formation of 1-(4-aminophenyl)-7-methyl-4,5-dihydroimidazo- and -1,2,3-triazolo[4,5-d]pyridazin-4-ones.     

New Efficient Synthesis of 5,6-Disubstituted-3-phenyl-1,2,3-triazolo[4,5-d]pyrimidin-7-ones via a Tandem Aza-Wittig Reaction

Twelve novel 5,6-disubstituted-3-phenyl-1,2,3-triazolo[4,5-d]pyrimidine-7-ones 5a–5l were designed and successfully synthesized via tandem aza-Wittig and annulation reactions of the corresponding iminophosphorances 2, aromatic isocyanate, and substituted thiophenols in satisfactory yields. The results from the preliminary bioassay indicated that some of these compounds possess inhibitory activities against the root and stalk of Brassica napus(rape) as well as Echinochloa crusgalli (barnyard grass) at the dosages of 100 mg/L and 10 mg/L, respectively.     

A convenient synthesis of 1,2,4-triazolo[4,3,2-o,p]-[1,3]diazocino[4,5-b]quinoxalines via a 1,3-dipolar cycloaddition reaction and a ring transformation

The reaction of 6-chloro-2-hydrazinoquinoxaline 4-oxide 5 with triethyl orthoformate gave 7-chloro-1,2,4-triazolo[4,3-a]quinoxaline 5-oxide 6. The reaction of compound 6 with phenyl isocyanate afforded 7-chloro-4-phenylamino-1,2,4-triazolo[4,3-a]quinoxaline 7 , while the reaction of compound 6 with phenyl isothiocyanate resulted in deoxygenation to provide 7-chloro-1,2,4-triazolo[4,3-a]quinoxaline 8. However, the reaction of compound 6 with allyl isothiocyanate effected the 1,3-dipolar cycloaddition reaction, but not deoxygenation, to furnish 9-chloro-4,5-dihydroisoxazolo[2,3-a][1,2,4]triazolo[3,4-c]quinoxalin-5-ylmethylisothiocyanate 9. Moreover, the reduction of compound 9 with iron/acetic acid resulted in ring transformation to give 11 -chloro-7-hydroxy-4-thioxo-4,5,6,7,8,9-hexahydro-1,2,4-triazolo[4,3,2- o,p][1,3]diazocino[4,5-b]quinoxaline 10 , whose acetylation afforded 5-acetyl-11-chloro-7-hydroxy-4-thioxo-4,5,6,7,8,9-hexahydro-1,2,4-triazolo[4,3,2-o,p][1,3]diazocino[4,5-b]quinoxaline 11.     

Convenient Synthesis of Some 1,2,4-triazolo[3,4-b]-1,3,4-thiadiazoles and 1,2,4-triazolo[3,4-b]-1,3,4-thiadiazines Bearing 3-Methylthio{7H-1,2,4-triazolo[1,5-d]tetrazol-6-yl}moiety as Possible Antimicrobial Activity

4-Amino-4H-3-methylthio{7H-1,2,4-triazolo[1,5-d]tetrazol-6-yl}-1,2,4-triazole-5thi-ol (1) was condensed with various substituted aromatic aldehydes or acid chlorides to yield a series of arylideneamines 2 or aroylamines 3. These were easily cyclized to the corresponding 6-aryl-3-methylthio7H-1,2,4-triazolo[1,5-d]tetrazol-6-yl-1,2,4-triazolo [3,4-b]-1,3,4-thiadiazoles (4) on treatment with palladium-on-charcoal or phosphorus oxychloride. Compounds 4 were also prepared directly via the reaction of 1 with aromatic carboxylic acids in the presence of phosphorus oxychloride. Cyclocondensation of 1 with a variety of two-carbon cyclizing reagents, namely chloroacetone, pyruvic acid, benzoylformic acid, and benzoin led to the formation of 3-methylthio{7H-1,2,4-triazolo[1,5-d]tetrazol-6-yl}-1,2,4-triazolo[3,4-b]-1,3,4-thiadiazines (5?8). Some of the newly synthesized compounds were tested for their antibacterial and antifungal activity against a variety of microorganisms.     

Synthesis and Crystal Structure of 3-Benzyl-5-cyclohexylamino-6-phenyl-3,6-dihydro-1,2,3-triazolo[4,5-d]pyrimidin-7-one

1 INTRODUCTION A large number of 8-azapurine (1,2,3-triazolo[4,5-d]pyrimidine) derivatives have been synthe-sized in recent years, and many of them are reportedto exhibit broad spectral biological activities, such asthe interesting antifungal[1], antiviral[2], anticancer[3]and antiallergic[4] properties. So far, these compoundshave been prepared by either of the following twomajor routes: annulation of a triazole ring onto apyrimidine ring or a pyrimidine ring onto a triazolering. Mos…     

4,5-二氢咪唑并[1,2-b]-1',2',4'-三唑-4-酮衍生物的合成与杀菌活性

应用芳基异氰酸酯与烯基膦亚胺1的氮杂Wittig反应,得到的碳二亚胺2,再与水合肼作用得到氨基咪唑啉酮衍生物4.而后用4与芳基异氰酸酯(或酰氯)、三苯基膦、六氯乙烷和三乙胺"一锅"反应,得到4,5-二氢咪唑并[1,2-b]-1',2',4'-三唑-4-酮衍生物6或7.探讨了所合成新型稠杂环化合物的生物活性,结果表明部分化合物表现出良好的杀菌活性.如7c在50mg/L浓度时,对棉花枯萎菌、稻瘟菌、黄瓜灰霉菌和油菜菌核菌的抑制率均达100%.     

[7+2]- and [11+2]-cycloaddition reactions of diazo-azoles with isocyanates to azolo[5,1-d] [1,2,3,5] tetrazine-4-ones

Diazo-azoles react as 1,7- or 1,11-dipoles with isocyanates to form the hitherto unknown pyrazolo[5,1-d] [1,2,3,5]tetrazine-4-ones, [1,2,3,5]tetrazino[5,4-b]indazole-4-ones and [1,2,3]triazolo[5,1-d][1,2,3,5]tetrazine-4-ones in a [7+2]- or [11+2]-cycloaddition reaction.     

1,2,3-Triazolo[4,5-e]-1,2,4-triazolo[3,4-c]pyrimidines

Some new 1,2,3-triazolo[4,5-e]-1,2,4-triazolo[3, 4 -c]pyrimidmes were prepared starting from the corresponding 1,2,3-triazolo[4,5-d]pyrimidines via the formation of the 1,2,4-triazole ring. Thus suitable hydrazino derivatives 6 were condensed with triethyl orthoformate, triethyl orthoacetate and triethyl orthobenzoate to give the expected tricyclic derivatives 7 , 8 and 9 . Intramolecular cyclization of the ethoxycarbonylhydrazino derivatives 10 gave the tricyclic compounds 11 bearing an hydroxyl group in the 3 position. The v-triazolo-s-triazolopyrimidine derivatives were tested towards the A₁ and A_2A adenosine receptors in binding assays, but they did not show any receptor affinity.     

Chemistry of furazano[3,4-b]pyrazine 6. 1,2,3-triazolo[4,5-b]furazano[3,4-b]pyrazines

The reduction of 1,2,3-triazolo[4,5-e]furazano[3,4-b]pyrazine 6-oxide was investigated. By means of data from x-ray crystallographic analysis it was shown that there is a relation between the aromaticity and the structure of the obtained triazoles.For communication 5, see [1].Latvian Institute of Organic Synthesis, Riga LV-1006. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1259–1264, September, 1998.     

New efficient synthesis of 2,5,6-trisubstituted oxazolo[5,4-d]pyrimidi-7(6H)-ones via an oxazolyliminophosphorane

A new efficient synthesis of 2,5,6-trisubstituted oxazolo[5,4-d]pyrimidi-7(6H)-ones by consecutive aza-Wittig reaction was developed. The sequential three-component reaction of oxazolyliminophosphorane 4, isocyanates and amines produced 2,5,6-trisubstituted oxazolo[5,4-d]pyrimidi-7(6H)-ones 7 in good overall yields in the presence of catalytic amount of EtONa.