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1.
A convenient synthesis of pyrrolo[3,2-d][1,3]oxazine-2,4-dione 4 is described and its reactivity towards various nucleophiles studied. The regioselective ring opening of anhydride 4 or its N-alkylated analog 25 in the presence of alanine or proline afforded, respectively, imidazolidinedione 22 and N-protected pyrrolo[3,2-e][1,4]diazepines 30 and 31 in a one-pot process. In a last part of this study, an alternative route to produce a library of eight non protected pyrrolo[3,2-e][1,4]diazepine-2,5-diones 35ah is described to overcome the limited reactivity of anhydride 4.  相似文献   

2.
The title compound 5 is synthesized by the reaction of the potassium salt of 3-aminobenzo[b]thiophene-2-carboxylic acid with phosgene. Compound 5 is readily alkylated to give 6 with methyl iodide, benzyl bromide, or propargyl bromide in the presence of sodium hydride. Reaction of 5 and 6 with nucleophiles follows specifically different pathways. Compound 5 is readily ionized to the isocycanate species 13 and subsequently reacts with methanol or methylamine to produce exclusively the carbamate 7 or ureido acid 9 . The N-substituted derivative 6 , in analogous reactions with methanol or methylamine, produce exclusively the amino ester 8 or the amino amide 10 . The N-benzyl derivative 6b reacts with the cyclic S-methylthiopseudourea 11 to give the tetracycle 12 , a new ring system.  相似文献   

3.
Oliver Lack 《Tetrahedron letters》2005,46(47):8207-8211
A two step parallel synthesis protocol for the preparation of 1N-substituted spirobenzodiazepineones is described. Treatment of 4-methyl-3,4-dihydro-1H-benzo[e][1,4]diazepine-2,5-dione with a series of alkyl halides using a microwave-assisted heating protocol provided N-derivatized compounds, which were transformed to the corresponding cyclopropylamines employing modified Kulinkovich-type reaction conditions. X-ray structural analysis gave conclusive evidence of the newly created spiro centre and revealed a significant flattening of the seven-membered ring system compared with the benzodiazepinedione system providing a characteristically different pattern of bond exit vectors. The physicochemical parameters log D, pKa, solubility and membrane permeability of both cyclopropanated and precursor compounds were assessed.  相似文献   

4.
A convenient synthesis of a series of pyrido[3,2-e][1,4]-diazepine-2,5-diones 8 and pyrido[2,3-e][1,4]diazepine-2,5-diones 9, is reported using the condensation of α-amino acid methyl ester derivatives with 1H-pyrido[3,2-d][1,3]oxazine-2,4-dione and 1H-pyrido[2,3-d][1,3]oxazine-2,4-dione. Compounds 8 and 9 were also synthesized by peptide coupling of α-amino acid methyl ester derivatives with β-amino acids (2 or 3) followed by the cyclisation in tetrahydrofuran with sodium hydride (NaH).  相似文献   

5.
( )-生物素,又称维生素H或辅酶R,化学名(3aS,4S,6aR)-六氢-2-氧-噻吩并[3,4-d]咪唑-4-戊酸,属于水溶性B族维生素,是整个生物界所必须的。生物素在维持动物正常发育,繁殖及保持皮肤、羽毛和骨骼健康中发挥重要作用。自1949年瑞士Roche公司首次开发化学全合成d-生物素后,经过几十  相似文献   

6.
7.
We have developed a method for synthesis of 1-methyl-4,5,7, 8-tetrahydro-6H-imidazo[4,5-e][1,4]diazepin-8-one. We have shown that in intramolecular cyclization of N-(2-hydroxyethyl)- or N-(2-chloroethyl)amides of 1-methyl-4-aminoimidazolyl-5-carboxylic acids it is not the corresponding tetrahydroimidazo[4,5-e][1,4]diazepin-8-ones which are formed but rather the isomeric 4-amino-5-(oxazolin-2-yl)imidazoles.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1203–1206, September, 1993.  相似文献   

8.
9.
A synthesis of 4-N-oxides and of 3-hydroxy derivatives of 1,3-dihydro-2H-benzofuro[3,2-e][1,4]diazepin-2-ones and of 2,3-dihydro-1H-benzofuro[3,2-e][1,4]diazepines is described. Condensation of 2-acetyl- and 2-benzoyl-3-ethoxycarbonylaminobenzofurans with acrylonitrile gave derivatives of 1,2-dihydro- and of 1,2,3,4-tetrahydrobenzofuro[3,2-b]pyridine.  相似文献   

10.
Several new pyrazolo[3,4-d]pyrimidine, pyrazolo[3,4-e][1,4]diazepine, pyrazolo[3,4-d][1,2,3]triazine and pyrolo[4,3-e][1,2,4]triazolo[1,5-c]pyrimidine derivatives were prepared by the reaction of the corresponding 5-amino-pyrazole-4-carbonitrile derivative with different organic reagents under different reaction conditions. Using IR, 1H NMR, and mass spectra we have characterized all new compounds.  相似文献   

11.
The reactions of halogenation, aminomethylation, acylation, and azo coupling in 1,3-dimethylpyrrolo[3,2-d]pyrimidine-2,4 dione proced at position 7, whereas nitration in acetic acid is directed primarily to position 6. In a num of cases, products of substitution of both hydrogen atoms in the pyrrole ring have been synthesized.Communication 11 from series Purines, pyrimidines, and condensed systems based on these compounds. For Communication 10, see [1].Rostov State University, Rostov-na-Donu 344104. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1242–1248, September, 1994. Original article submitted September 6, 1994.  相似文献   

12.
Reaction of 5-amino-1,3-dimethylpyrrolo[3,2-d]pyrimidine-2,4-(1H,3H)-diones with -diketones produces enaminoketones. Some of these are converted by Lewis acids into pyrrolopyridazines.For No. 2, see [1].Rostov-on-Don State University, Rostov-on-Don 344090, Russia; e-mail: zeb@chimfak.rud.runnet.ru. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 375–380, March, 1999.  相似文献   

13.
Conclusions Derivatives of 2-oxo-2,3-dihydro-1H-thieno[3,4-d]imidazole were synthesized from 4,5-di-substituted 2-imidazolinones.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2381–2383, October, 1987.  相似文献   

14.
15.
The xanthine homolog 4,5,7,8-tetrahydro-6H-imidazo[4,5-e][1,4]diazepine-5,8-dione has been synthesized in four stages from cyanoacetamide.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 511–512, April, 1992.  相似文献   

16.
The synthesis of a cyclic homolog of caffeine is reported. Its 2-nitro- and 2-amino derivatives were obtained for the first time. It was shown that the 2-bromo and 2-chloro substituted cyclic homologs react with nucleophiles under basically identical conditions. Whereas 8-bromocaffeine can give a normal Ullman reaction product via heating with powdered copper in ethylene glycol, the homolog gives only a reduction product and does not react with potassium thiocyanate or cyanide.A. V. Bogatskii Physicochemical Institute, National Academy of Sciences of Ukraine, Odessa 270080. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 824–827, June, 1988.  相似文献   

17.
Cyclization of thioglycolic acids derivatives 3a-d gave isoindolo[1,2-b]thieno[2,3(3,2 or 3,4)-e][1,3]-thiazocines 4a-d . Isoindolo[2,1-a]thieno[2,3(3,2 or 3,4)-f][1,4] or [1,5]diazocines 10b or 11a-c were synthesized from Beckmann or Schmidt rearrangement of the ketones 7a-c .  相似文献   

18.
Russian Journal of General Chemistry - A method was developed for the synthesis of new fused amines, thieno[3,2-d]pyrimidine derivatives, starting from the corresponding chloride and various...  相似文献   

19.
The synthetic pathway leading to 5,6-dihydro-4H-furo[3,2-f]pyrrolo[1,2-a][1,4]diazepines is described in four steps starting from α-bromophenones via 2-amino-3-furonitriles.  相似文献   

20.
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