共查询到20条相似文献,搜索用时 31 毫秒
1.
G. V. Mokrov A. M. Likhosherstov V. P. Lezina T. A. Gudasheva I. S. Bushmarinov M. Yu. Antipin 《Russian Chemical Bulletin》2011,60(8):1694-1702
Reactions of methyl 2-(2-formyl-1H-pyrrol-1-yl)alkanoates with unsubstituted aliphatic 1,2-, 1,3-, and 1,4-diamines gave N-unsubstituted pyrrolo[2,1-c]-1,3-diazacycloalkano[1,2-a]-pyrazinones. Some of them show ring-chain tautomerism. Transformations of these compounds led to a number of novel heterocyclic systems: 2,10-dihydro-3H,5H-imidazo[1,2-a]-pyrrolo[1,2-d]pyrazines, 2,3,4,11-tetrahydro-6H-pyrrolo[1??,2??:4,5]pyrazino[1,2-a]pyrimidines, 1,2,3,5,6,10b-hexahydroimidazo[1,2-a]pyrrolo[2,1-c]pyrazines, 1,3,4,6,7,11b-hexahydro-2H-pyrrolo[2??,1??:3,4]pyrazino[1,2-a]pyrimidines, and 2,3,4,5,6,7-hexahydro-1H-pyrrolo[2,1-c]-[1,4,7]triazacycloundecin-8(9H)-one. 相似文献
2.
Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described. 相似文献
3.
N-Methylimidazole reacts with bis-imidoylchlorides derived from oxalic acid and yields new bis-cationic tricyclic systems of type of diimidazo[1,2-a:2′,1′-c]pyrazines. Under identical conditions, 1,2-dimethylimidazole has been transformed into pyrrolo[1,2-a]imidazoles. 2,2′-Biimidazole itself can be cyclized with bis-imidoylchlorides thus yielding a new heterotricycle, which possesses two different 1,4-diaza-1,3-diene substructures. 相似文献
4.
Loreto Legerén 《Tetrahedron letters》2010,51(31):4053-5080
Alkylation of l-prolinamide with 3-(chloromethyl)-2-halopyridines, followed by cyclization through an intramolecular Pd-catalysed amidation, provided an entry to the pyrido[2,3-e]pyrrolo[1,2-a][1,4]diazepin-10-one scaffold. Furthermore, a synthetic route towards diverse new pyrido[f]pyrrolo[1,2-a][1,4]diazepin-7-ones has been developed by acylation of contiguously substituted (aminomethyl)halopyridines with Boc-l-proline followed by intramolecular amination. 相似文献
5.
An efficient, one-pot, multi-component synthesis of 3-amino-2-arylimidazo[1,2-a]pyridines, 3-amino-2-arylimidazo[1,2-a]pyrazines, and 3-amino-2-arylimidazo[1,2-a]pyrimidines is described. Heating a mixture of a 2-aminopyridine, 2-aminopyrazine or 2-aminopyrimidine, a benzaldehyde, and imidazoline-2,4,5-trione under solvent-free conditions afforded imine derivatives of the title compounds in excellent yields. Single-crystal X-ray analysis conclusively confirms the structure of these bridgehead bicyclic 5-6 heterocycles. 相似文献
6.
2,4,7-Trisubstituted hydrogenated pyrazino[1,2-a]pyrazines as potential β-turn mimetics were prepared for the first time in a stereoselective synthesis from hexahydro[1,2,3]triazolo[1,5-a]pyrazines. 相似文献
7.
Vincent Gaumet Emmanuel Moreau Abbass Taleb Johan Neyts Claire Lartigue Olivier Chavignon Alain Gueiffier Jacques Métin 《Tetrahedron letters》2010,51(47):6082-6085
Access to N-protected or N-free imidazo[1,2-a]pyrrolo[3,2-c]pyridine derivatives as potential antiviral compounds was achieved in good yields from N-protected 7-amino-8-halo-2-methylimidazo[1,2-a]pyridines by catalytic coupling of terminal acetylenes under mild conditions using [PdCl2(PPh3)2] or [Cu(Phen)(PPh3)2]NO3. 相似文献
8.
Kazuhiro Kobayashi Yasutoshi Himei Shuhei Fukamachi Miyuki Tanmatsu Osamu Morikawa Hisatoshi Konishi 《Tetrahedron》2007,63(20):4356-4359
Heating mixtures of 2-(pyrrol-1-yl)benzaldehydes and aryl amines under argon afforded 9-arylamino-9H-pyrrolo[1,2-a]indoles, via cyclization of the resulting 2-(pyrrol-1-yl)benzaldimine intermediates. Heating in the presence of oxygen afforded (Z)-9-arylimino-9H-pyrrolo[1,2-a]indoles, which were successfully hydrolyzed with hydrochloric acid to give pyrrolo[1,2-a]indol-9-ones. 相似文献
9.
Alexander I. Zbruyev 《Tetrahedron》2007,63(20):4297-4303
A convenient and effective synthetic approach to potentially radiochromic polyarene derivatives of bi- and tricyclic aziridines utilizing modified Suzuki-Miyaura cross-coupling with catalysis in micellar media has been developed. A series of polyarene substituents were introduced into 1,5-diaryl-3,5a-dihydro-1H-azireno[1,2-c]imidazoles, 1,6-diaryl-1,3,4,6a-tetrahydroazireno[1,2-a]pyrazines, and 1,2-diaryl-1,1a-dihydroazireno[1,2-a]quinoxalines without degradation of the highly reactive aziridine ring system. 相似文献
10.
Hussein El-Kashef Sylvain Rault Jean-Charles Lancelot Max Robba 《Journal of heterocyclic chemistry》1986,23(1):161-167
The synthesis of several [1]benzothieno[2,3-e]pyrrolo[1,2-a]pyrazines and other related heterocycles has been described. A study of the nmr spectra of these compounds was also reported. 相似文献
11.
Sachin D. Pardeshi Bhausaheb N. Patil Prashant Patil Atul C. Chaskar 《Tetrahedron letters》2019,60(47):151250
A convenient Pictet-Splengler approach for the synthesis of substituted pyrrolo[1,2-a]quinoxalines from aryl amine and 1-(2-aminoaryl)-pyrrole has been developed. This is the first domino protocol involving formation of benzaldehyde as an intermediate from benzyl amines and benzyl alcohols using 1,2-DNB as an oxidant, followed by its endo cyclization with 1-(2-aminophenyl)-pyrrole to furnish the pyrrolo[1,2-a]quinoxalines. Notably, this procedure exhibits good functional group tolerance as well as good to moderate yield of pyrrolo[1,2-a]quinoxaline. 相似文献
12.
The reaction of β-lactam carbenes with 3,6-di(2-pyrimidinyl)tetrazine was studied, which produced good yields of novel 5-(3-[1,2,3]triazolo[1,5-a]pyrimidinyl)pyrrol-2-ones or pyrrolo[3′,2′:3,4]pyrrolo[1,2-a]pyrimidin-2-ones under heating at 100 °C or 140 °C, respectively. This work provided a highly efficient strategy for the construction of both [1,2,3]triazolo[1,5-a]pyrimidine and pyrrolo[3′,2′:3,4]pyrrolo[1,2-a]pyrimidine ring systems from the same reactants, and extended the application of β-lactam carbenes in the syntheses of complex heterocycles. 相似文献
13.
We herein report the efficient and convenient synthesis of 6-substituted-5H-pyrrolo[2,3-b]pyrazines. The reaction is a palladium-catalyzed heteroannulation process followed by deprotection to yield the desired pyrrolo[2,3-b]pyrazine substrates. The reaction starts with readily accessible N-(3-chloropyrazin-2-yl)-methanesulfonamide and commercially available terminal alkynes and works with aryl- and alkylalkynes. 相似文献
14.
V. I. Terenin E. A. Sumtsova E. V. Kabanova A. P. Pleshkova N. V. Zyk 《Chemistry of Heterocyclic Compounds》2004,40(4):436-445
Esters, nitriles, and amides of dipyrrolo[1,2-a:2',1'-c]pyrazines have been synthesized by the acylation of dipyrrolo[1,2-a:2',1'-c]pyrazines and 5,6-dihydrodipyrrolo[1,2-a:2',1'-c]pyrazines with trichloroacetic acid chloride, p-tosyl isocyanate, and isocyanatophosphoric acid dichloride (Kirsanov isocyanate). 相似文献
15.
Rustam T. Iminov Andrey A. Tolmachev Yulian M. Volovenko Oleg V. Shishkin 《Tetrahedron》2009,65(41):8582-586
The reaction of 2-aminobenzamides with 2-oxocyclopentane-, 2-oxocyclohexane-, and 2-oxocycloheptaneacetic acids esters was found to give 7a,8,9,10-tetrahydrocyclopenta[2,3]pyrrolo[1,2-a]quinazoline-6,12(7H,11H)-diones, 7,7a,8,9,10,11-hexahydro-6H-indolo[1,7a-a]quinazoline-6,13(12H)-diones, and 7a,8,9,10,11,12-hexahydrocyclohepta[2,3]pyrrolo[1,2-a]quinazoline-6,14(7H,13H)-diones, respectively. The relative configuration with the cis-fused butyrolactam and cycloalkane rings was assigned to the prepared compounds on the basis of an X-ray crystallographic study. 相似文献
16.
Nehal M Elwan 《Tetrahedron》2004,60(5):1161-1166
Reaction of 2-cyanomethylbenzimidazole 1 with hydrazonoyl halides 2 led to formation of pyrrolo[1,2-a]benzimidazole derivatives 7. Similar reaction of 1 with halides 3 afforded 5-amino-4-(benzimidazol-2-yl)pyrazole derivatives 11 or 1-amino-2-arylpyrazolo[3,4:4′,3′]pyrrolo[1,2-a]benzimidazol-4-one 14 depending on the reaction conditions. The mechanisms of the studied reactions are discussed. 相似文献
17.
V. I. Terenin E. V. Kabanova N. A. Tselishcheva M. A. Kovalkina A. P. Pleshkova N. V. Zyk 《Chemistry of Heterocyclic Compounds》2004,40(3):351-360
The direction of trifluoroacetylation with trifluoroacetic anhydride of 3,4-dihydropyrrolo[1,2-a]pyrazines containing an alkyl or aralkyl substituent in position 1 depends on both the structure of the 3,4-dihydropyrrolo[1,2-a]pyrazine starting materials and on the ratio of reagent:substrate. It may lead to both mono- and disubstituted products. Trifluoroacetylation of 1-methyl-3,4-dihydropyrrolo[1,2-a]pyrazines occurs at the methyl group. Acetylation of 3,4-dihydropyrrolo[1,2-a]pyrazines leads only to N-acetyl-substituted reaction products. 相似文献
18.
Ho Sik Kim Yoshihisa Kurasawa Chiemi Yoshii Minako Masuyama Atsushi Takada Yoshihisa Okamoto 《Journal of heterocyclic chemistry》1990,27(4):1115-1117
The reaction of the 2-substituted 6-chloroquinoxaline 4-oxides 1a or 1b with 2-fold molar amount of methyl propiolate resulted in the 1,3-dipolar cycloaddition reaction to give 8-chloro-1,3-bismethoxycarbonyl-4-(piperidin-1-yl)pyrrolo[1,2-a]quinoxaline 4a or 8-chloro-1,3-bismethoxycarbonyl-4-(morpholin-4-yl)pyrrolo-[1,2-a]quinoxaline 4b , respectively. Compound 4a or 4b was transformed into 8-chloro-3-methoxycarbonyl-4-(piperidin-1-yl)pyrrolo[1,2-a]quinoxaline 5a or 8-chloro-3-methoxycarbonyl-4-(morpholin-4-yl)pyrrolo[1,2-a]-quinoxaline 5b , respectively. The structure of 4a,b was confirmed by the NOE measurement among the C1 -H , C 2-H and C 9-H proton signals of 5a,b . An additional reaction mechanism was proposed for the ring transformation of isoxazolo[2,3-a]quinoxalines into pyrrolo[1,2-a]quinoxalines. 相似文献
19.
Didier Legroux Jean-Paul Schoeni Christiane Pont Jean-Pierre Fleury 《Helvetica chimica acta》1987,70(1):187-195
2-Aza-1,3-dienes. Access to N-Aminoimidazoles, 3H-Pyrroles, [1,2,4]Triazolo[1,5-a]pyrazines, or Imidazo[1,2-a]pyrazines Nucleophilic attack of 5-(dialkylamino)-2-aza-1,3-diene-1,1-dicarbonitriles (or their 1-methoxycarbonyl analogous) by hydrazines or hydrazdes gives substituted N-aminoimidazoles, [1,2,4]triazolo-[1,5-a]pyrazines, or α-dihydrazino derivatives. With α-amino esters (or analogous), imidazo[1,2-a]pyrazines are produced. Addtion of cyanide anions occurs also with formation of substituted 3H-pyrroles. Structures and rationalisation of this nucleophilic attack are discussed. 相似文献
20.
Treatment of N-alkyl-N-allyl-pyrrolo-2-carboxamides with catalytic amounts of palladium derivatives gave regioselectively intramolecular cyclizations to generate bicyclic pyrrolo-fused structures. Pyrrolo[1,2-a]pyrazin-1-ones were achieved in high yields by an amination reaction, while pyrrolo[2,3-c]pyridin-7-ones and pyrrolo[3,2-c]pyridin-4-ones were obtained by an oxidative coupling process. 相似文献