Bildungs‐und Zersetzungs‐Erscheinungen bei Thioharnstoffen

Abstract

Nach S c h o t t e n -B a urn a n n erhiilt man das B e n z o y 1 d e r i vat.Weisse Nadeln aus hoch siedendem Ligro'in, Schmp. 1900, schwer lijslich in Alkohol, Essigester, unlijslich in Wasser und Aceton.

A Facile Synthesis of 6,7-Fused Steroidal Thiazoles via 1,3-Intramolecular Migration of Bromine/Allylic Displacement of Bromine

“…10 Due to the significance of thiazole derivatives in medicinal chemistry, considerable effort has been devoted to develop alternate routes for their synthesis. [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28] Although several strategies with variable yields have been reported for the synthesis of steroidal as well as non-steroidal thiazoles, the Hantzsch's protocol [29][30][31] continues to be a method of choice involving the reaction of α-halocarbonyl compound with an appropriate thiourea or thioamide. Thus, we have also selected the Hantzsch's protocol for this purpose, 5-bromosteroidal ketones, [32][33] are selected instead of 7-bromosteroidal ketones because both lead to the same product but preparation of 7-bromocholestan-6-one [20][21] is much more tedious leading to a mixture of products.…”