6-Methylsalicylic Acid Synthase Activity

Acyl-CoA:malonyl-CoA C-Acyltransferase (Decarboxylating, Oxoacyl-Reducing, Thioester-Hydrolysing and Cyclizing)

Catalysis of the reaction: acetyl-CoA + 3 H(+) + 3 malonyl-CoA + NADPH = 6-methylsalicylate + 3 CO(2) + 4 CoA + H(2)O + NADP(+).