Structures of ent-herbertane sesquiterpenoids displaying antifungal properties from the liverwort Herberta adunca

Abstract

Several aromatic sesquiterpenoids displaying antifungal properties have been isolated from the liverwort Herberta adunca together with a mother hydrocarbon with a novel irregular sesquiterpene skeleton, entherbertane, and their structures and absolute configurations have been determined on the basis of extensive degradation reactions and spectroscopic evidence. The biological activity is also described. ' B. cinerea R. solani P. debaryanum * B. cinerea R. solani P. debaryanum * B . cinerea R. solani ~ P. debaryanum Concentration (p.p.m.)

Chemical Constituents of Malagasy Liverworts, Part II: Mastigophoric Acid Methyl Ester of Biogenetic Interest from Mastigophora diclados (Lepicoleaceae Subf. Mastigophoroideae)

“…Compound 14 was obtained as an amorphous powder with the molecular formula of C 16 12) except for the absence of the downfield methyl signal at d 2.25 of 2 in the 1 H-NMR of 14, suggesting that the ester group was located at C-12. This fact was confirmed by the downfield shifts (while comparing to those of 2) of the aromatic proton signals.…”

“…12) In order to obtain more antimicrobial data for herbertenoids, compounds 2-4, 9, 14, 16 and (Ϫ)-1,2-dihydroxyherberten-12-al (18) were tested against Staphyloccocus aureus strain by agar diffusion. Although the herbertenoids tested showed weaker activities than the standard antibiotics used as control [chloramphenicol (22 mm) and kanamycin (23 mm)], Mastigophorene C (9), which is a dimer of herbertene-1,2-diol (4), exhibited the strongest inhibition (17 mm) while its monomer displayed significant activity (13 mm).…”

“…The remaining extract was chromatographed on silica gel to afford eighteen fractions. Each fraction was purified with size exclusion chromatography by Sephadex LH-20, silica gel and preparative HPLC or TLC to yield a-and b-herbertenols (2, 3), 12,13) herbertene 1,2-diol (4), sandaracopimaric acid and ent-pimara-8 (14), 15-dien-19-oic acid, 14,15) mastigophorene C and D (9, 10), 2,3) riccardin C (15), 16) a-formylherbertenol (16), 12) stigmasterol, mastigophoric acid methyl ester (14) and a mixture of two cycloartenyl esters (17). The known compounds were identified by comparison of their spectral data with those of authentic samples and those reported in the literature.…”

Lipase‐Promoted Access to Phenolic Herbertane‐Type Sesquiterpenes: (+)‐1,14‐Herbertenediol, (−)‐α‐Herbertenol, (−)‐Herbertenediol and Their Enantiomers

“…[1] Isolation of (Ϫ)-α-herbertenol (2) and (Ϫ)-herbertenediol (3), along with other herbertenes, from the liverwort Herberta adunca was reported earlier by Matsuo and co-workers. [2] Figure 1 The presence of two vicinal quaternary carbon atoms on the cyclopentane ring, and their associated biological activities, make phenolic herbertanes interesting synthetic targets of current interest, and significant numbers of racemic [3] or enantioselective [4] syntheses have been reported. We have recently described a lipase-catalyzed kinetic resolution for the enantioselective approach toward cuparanetype sesquiterpenoids.…”

New Pimarane-Type Diterpenoid and ent-Eudesmane-Type Sesquiterpenoid from Bornean Liverwort Mastigophora diclados

“…A total of six known compounds have been isolated, including 4-epi-sandaracopimaric acid (2) [11], rosa-1(10),15-dien-18-oic acid (3) [12], herbertene (4) [13], -herbertenol (5) [13], herbertene-1,2-diol (6) [13], and ent-7-hydroxyeudesm-4-en-6-one (7) [14]. Furthermore, an enantiomer of eudesmane, ent-chlorantene G (8) [15].…”