Three New Lanostane Triterpenoids, Inonotsutriols A, B, and C, from <i>Inonotus obliquus</i>

Abstract

Abstract Three new lanostane‐type triterpenoids, inonotsutriols A ( 1 ), B ( 2 ), and C ( 3 ) were isolated from the sclerotia of Inonotus obliquus ( Pers .: Fr.) (Japanese name: kabanoanatake; Russian name: chaga). Their structures were determined to be (3 β ,21 R ,24 S )‐21,24‐cyclolanost‐8‐ene‐3,21,25‐triol ( 1 ), (3 β ,21 R ,24 R )‐21,24‐cyclolanost‐8‐ene‐3,21,25‐triol ( 2 ), and (3 β ,21 R ,24 S )‐21,24‐cyclolanosta‐7,9(11)‐diene‐3,21,25‐triol ( 3 ) on the basis of NMR spectroscopy including 1D and 2D experiments ( 1 H, 1 H‐COSY, NOESY, HMQC, and HMBC) and EI‐MS.