Keiko Inoue

Antimicrobial agents from Bletilla striata

Abstract Three new bibenzyls and two new dihydrophenanthrenes, which exhibit antimicrobial activity, were isolated from tubers of Bletilla striata. They were identified by various spectroscopic methods.

Biphenanthrenes from Bletilla striata

Abstract From tubers of Bletilla striata , three new biphenanthrenes were isolated, together with batatasin Ill and 3′-O-methylbatatasin III. The structures were elucidated from their spectroscopic data.

Blestrianol A, B and C, biphenanthrenes from Bletilla striata

Abstract Three biphenanthrenes, blestrianol A, B and C and one dibenzylphenanthrene were isolated from tubers of Bletilla striata . The structures were elucidated as 4,4′-dimethoxy-9,9′,10,10′-tetrahydro-[1′,3-biphenanthrene]-2,2′,7,7′-tetraol, 4′,5-dimethoxy-8-(4-hydroxybenzyl)-9,9′,10,10′-tetrahydro-[1′,3-biphenanthrene]-2,2′,7,7′-tetraol,4′,5-dimethoxy-8-(4-hydroxybenzyl)-9,10-dihydro-[1′,3-biphenanthrene]-2,2′,7,7′-tetraol and 1,8-bi(4-hydroxybenzyl)-4-methoxy-phenanthrene-2,7-diol by their spectroscopic data.

Stilbenoids from Bletilla striata

Abstract Five new stilbenoids, three bibenzyls, one dibenzyldihydrophenanthrene and one benzoyldihydrophenanthrene, were isolated from tubers of Bletilla striata . The new structures were elucidated as 3,3′-dihydroxy-4-( p -hydroxybenzyl)-5-methoxybibenzyl, 3,3′-dihydroxy-2-( p -hydroxybenzyl)-5-methoxybibenzyl, 3′,5-dihydroxy-2-( p -hydroxybenzyl)-3-methoxybibenzyl, 2,7-dihydroxy-1,3-bi( p -hydroxybenzyl)-4-methoxy-9,10-dihydrophenanthrene and 2,7-dihydroxy-1-( p -hydroxybenzoyl)-4-methoxy-9,10-dihydrophenanthrene, by their spectroscopic data.

Benzylphenanthrenes from Bletilla striata

Abstract Three benzylphenanthrenes were isolated from tubers of Bletilla striata and their structures elucidated by spectroscopic methods. The structures of previously isolated dihydrophenanthrene were revised by NOE experiments.

Methylated stilbenoids from Bletilla striata

Abstract From tubers of Bletilla striata , four permethylated stilbenoids were isolated together with 3,5-dimethoxybibenzyl and the anthraquinone, physcion. The new structures were elucidated as 2,4,7-trimethoxy-phenanthrene, 2,4, 7-trimethoxy-9,10-dihydrophenanthrene, 2,3,4,7-tetramethoxyphenanthrene and 3.3′,5-trimethoxybibenzyl on the basis of spectroscopic data.

Phenanthrene glucosides from Bletilla striata

Abstract Four phenanthrene glucosides were isolated from tubers of Bletilla striata . The structures were elucidated as 2,7-dihydroxy-4-methoxyphenanthrene-2- O -glucoside, 2,7-dihydroxy-4-methoxyphenanthrene-2,7- O -diglucoside, 3,7-dihydroxy-2,4-dimethoxyphenanthrene-3- O -glucoside and 2,7-dihydroxy-1-(4′-hydroxybenzyl)-9,10-dihydrophenanthrene-4′- O -glucoside, on the basis of spectroscopic data.

Blestrin A and B, bis(dihydrophenanthrene)ethers from Bletilla striata

Abstract Two new bis(dihydrophenanthrene)ethers were isolated from tubers of Bletilla striata . The structures were elucidated from their spectroscopic data.

Bisphenanthrene ethers from Bletilla striata

Abstract From tubers of Bletilla striata , bisphenanthrene ethers were isolated and their structures were elucidated from their spectral data and X-ray analysis.

Three dihydrophenanthropyrans from Bletilla striata

Abstract From tubers of Bletilla striata , three new dihydrophenanthropyran derivatives, bletilols A, B and C were isolated. The structures were elucidated to be 4-acetoxy-11-methoxy-3-(4′-hydroxy-3′,5′-dimethoxyphenyl)-3,4,5,6-tetrahydro-2H-phenanthro[2,1-b]pyran-8-ol, 4-acetoxy-11-methoxy-3-(4′-hydroxy-3′-methoxyphenyl)-3,4,5,6-tetra-hydro-2H-phenanthro[2,1-b]pyran-8-ol, and 4-acetoxy-6-methoxy-3-(4′-hydroxy-3′-methoxyphenyl)-3,4,10,11-tetrahydro-2H-phenanthro[2,3-b]pyran-8-ol, respectively, on the basis of spectroscopic data.