Abstract: A position 12-substituted mutilin derivative, a novel mutilin analogue, is provided that exhibits strong antimicrobial activity against abroad spectrum of Gram-positive or Gram-negative bacteria, including various drug-resistant bacteria, as well as intermediates for the production of such mutilin derivatives. Specifically, a mutilin derivative or an acid-addition salt thereof is provided that is represented by the following chemical formula (1): (wherein R1 is a hydrogen atom, a formyl group, a substituted or unsubstituted lower alkyl group, an aralkyl group whose aromatic ring may be optionally substituted, a heteroaralkyl group whose aromatic ring may be optionally substituted or a lower alkyloxycarbonyl group; and R2 is a hydrogen atom, a lower alkyl group or an aralkyl group whose aromatic ring may be optionally substituted) (R1 is neither an ethyl group nor a vinyl group).