Process development of a large-scale synthesis of TKA731: A tachykinin receptor antagonist

M Prashad, D Har, B Hu, HY Kim…

Index: Prashad, Mahavir; Har, Denis; Hu, Bin; Kim, Hong-Yong; Repic, Oljan; Blacklock, Thomas J Organic letters, 2003 , vol. 5, # 2 p. 125 - 128

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Citation Number: 14

Abstract

An efficient and chromatography-free large-scale synthesis of a tachykinin receptor antagonist TKA731 (1), utilizing the coupling of dipeptide 7 and 2-chloro-4 (3H)- quinazolinone (13) as the key step, is described. The overall yield of 1 from BOC-l-3-(2- naphthyl) alanine (2) in six linear steps (total of eight steps) is 63%. This new convergent approach avoided the use of methyl iodide and the formation of methanethiol byproduct in ...