Complestatin is a compound extracted from Streptomyces lavendulae mycelia; on acid hydrolysis yields D-4-hydroxyphenylglycine & D-3,5-dichloro-4-hydroxyphenylglycine & acidic chromophore; inhibits gp120-CD4 binding. It is isolated from the culture broth of Streptomyces and has anti-HIV-1 activity. It has a role as a metabolite, an antimicrobial agent and an anti-HIV-1 agent.