A synthesis of 1-substituted 5-[2-(acylamino)ethyl]-1H-pyrazole-4-carboxamides
摘要:
A seven-step synthesis of 1-substituted 5-(2-acylaminoethyl)-1H-pyi-azole-4-carboxamides 20 as the pyrazole analogues of histamine was developed. The synthesis starts with a three-step preparation of N(1)-substituted methyl 5-(2-tert-butoxycarbonylaminoethyl)-1H-pyrazole-4-carboxylates 7 from commercially available Boc-beta-alanine (1). Subsequent four-step transformation of the key-intermediates 7 into the final products 20 was performed following two complementary reaction sequences comprising acidolytic removal of the Boc group, hydrolysis of the COOMe group, amidations of the COOH group, and acylations of the NH2 group. The Structures of pyrazole derivatives were determined by spectroscopic methods and by X-ray diffraction. (C) 2009 Published by Elsevier Ltd.
A synthesis of 1-substituted 5-[2-(acylamino)ethyl]-1H-pyrazole-4-carboxamides
摘要:
A seven-step synthesis of 1-substituted 5-(2-acylaminoethyl)-1H-pyi-azole-4-carboxamides 20 as the pyrazole analogues of histamine was developed. The synthesis starts with a three-step preparation of N(1)-substituted methyl 5-(2-tert-butoxycarbonylaminoethyl)-1H-pyrazole-4-carboxylates 7 from commercially available Boc-beta-alanine (1). Subsequent four-step transformation of the key-intermediates 7 into the final products 20 was performed following two complementary reaction sequences comprising acidolytic removal of the Boc group, hydrolysis of the COOMe group, amidations of the COOH group, and acylations of the NH2 group. The Structures of pyrazole derivatives were determined by spectroscopic methods and by X-ray diffraction. (C) 2009 Published by Elsevier Ltd.
A synthesis of 1-substituted 5-[2-(acylamino)ethyl]-1H-pyrazole-4-carboxamides
作者:David Kralj、Miha Friedrich、Uroš Grošelj、Sonja Kiraly-Potpara、Anton Meden、Jernej Wagger、Georg Dahmann、Branko Stanovnik、Jurij Svete
DOI:10.1016/j.tet.2009.06.021
日期:2009.8
A seven-step synthesis of 1-substituted 5-(2-acylaminoethyl)-1H-pyi-azole-4-carboxamides 20 as the pyrazole analogues of histamine was developed. The synthesis starts with a three-step preparation of N(1)-substituted methyl 5-(2-tert-butoxycarbonylaminoethyl)-1H-pyrazole-4-carboxylates 7 from commercially available Boc-beta-alanine (1). Subsequent four-step transformation of the key-intermediates 7 into the final products 20 was performed following two complementary reaction sequences comprising acidolytic removal of the Boc group, hydrolysis of the COOMe group, amidations of the COOH group, and acylations of the NH2 group. The Structures of pyrazole derivatives were determined by spectroscopic methods and by X-ray diffraction. (C) 2009 Published by Elsevier Ltd.