A Short Synthesis of Benzomorphane Analgesics (±)-Metazocine and (±)-Phenazocine

Abstract

A three step synthesis of (±)-metazocine and (±)-phenazocine starting with 3,4-lutidine is described. The key step involves Lewis acid promoted lithiation/electrophilic substitution reaction of N-alkyl-3,4-dimethyl-1,2,5,6- tetrahydropyridine.

Keywords:

• Analgesics
• α-azacarbanion
• Lewis acid
• lithiation
• (±)-metazocine
• (±)-phenazocine

ACKNOWLEDGMENT

Financial support from CSIR (Scheme no. 01(2138)/07/EMR-II), New Delhi, India is gratefully acknowledged.