Diterpene Research Articles

Chemical and chemotaxonomic researches for pterophyten 52. Components of Scypholepia hookerianaJ.Sm.

The fronds of Scypholepia hookeriana J. SM. (Microlepia hookeriana (WALL.) PRESL) afforded four oligoglycosides of a new ent-pimarane-type diterpene, which were named hookerosides A (I), B (II), C (III) and D (IV). The structures were elucidated by means of chemical reactions and spectroscopic methods to be 3α-[O-(3-O-methyl)-α-L-rhamnopyranosyl-(1→2)-α-L-arabinofuranosyloxy]-12α-[(3-O-methyl)-β-D-quinovopyranosyloxy]-(I), 3α-[O-(3-O-methyl)-α-L-rhamnopyranosyl-(1→2)-α-L-arabinofuranosyloxy]-12α-[β-D-fucopyranosyloxy]-(II), 3α-[O-(3-O-methyl)-β-D-glucopyranosyl-(1→2)-α-L-arabinofuranosyloxy]-12α-[β-D-fucopyranosyloxy]-(III) and 3α-[O-β-D-fucopyranosyl-(1→3)-O-β-D-fucopyranosyl (1→2)-α-L-arabinofuranosyloxy]-12α-[β-D-fucopyranosyloxy]-(IV) ent-pimara-8 (14), 15-diene.

Structure of helioscopinolide A, C20H28O3, a novel diterpene

Structure of helioscopinolide A, C20H28O3, a novel diterpene

Diterpenoids from Baccharis tola

ent-4α-Hydroxy-19-norbeyer-15-ene, ent-beyer-15-en-17,19-diol, apigenin and two new diterpenes, ent-beyer-15-en-18,19-diol and 15β,16β-epoxide- ent-beyeran-18-ol were isolated from Baccharis tola.

New deterpenes from Spongia officinalis

Four new diterpenes has been isolated from Spongia officinalis and their structures determined on the basis of spectral and chemical evidence.

Antifeeding Activities of Chlordimeform and Some Plant Diterpenes When Injected into Tabacco Cutworm

クロルジメホルムおよび植物ジテルペンをハスモンヨトウ幼虫に注射して摂食阻害作用を調べた. 薬量の対数と摂食阻害率プロビットとは明らかな直線関係があった. 非絶食幼虫において, AC50では clerodin>caryoptin>clerodendrin-A≒clerodendrin-B>chlordimeform, AC95では, clerodin>caryoptin≒clerodendrin-B>clerodendrin-A≒chlordimeform の順に効力が高かった. 高濃度の chlordimeform を注射した幼虫は摂食行動の異常を示し, 体のねじり, 頭の回転などが多くなり, 興奮した. 天然ジテルペン化合物は強い摂食阻害作用を示すが興奮とかその他の異常行動はみられなかった. chlordimeform と天然ジテルペンによる症状のちがいはこの昆虫における作用機構のちがいを示すものである.

4-deoxyphorbol and 4α-deoxyphorbol aldehydes new diterpenes and their esters

Two diterpenes were isolated from Sapium indicum L. The first was 12-[2 -methylaminobenzoyl]-4-deoxyphorbaldehyde-13-acetate and the second its 4α-isomer. These compounds are the first natural tiglianes to exhibit a C-20 aldehyde.

Poilaneic acid, a cembranoid diterpene from Croton poilanei

Poilaneic acid, a cembranoid diterpene from Croton poilanei, has been characterized as (1 R*,2 E,4 Z,7 E, 11 Z)-12-carboxyl-1-isopropyl-4,8-dimethylcyclotetradecatetraene.

Diterpenoids from Micrandropsis scleroxylon

The structure of micrandrol-C from Micrandropsis scleroxylon (Euphorbiaceae) is revised to 2,6-dihydroxy-7-methyl-1-methylthiophenanthrene. This and other micrandrols are probably diterpenes in view of their co-occurrence with micrandrol-D, the hemiketal of 1,2,3,4,9,10-hexahydro-6-hydroxy-4a-hydroxymethyl-1,1,7-trimethy-2-oxophenanthrene.

Structure of 3.alpha.-hydroxy-15-rippertene. Evidence for 1,2-methyl migration during biogenesis of a tetracyclic diterpene in termites

Structure of 3.alpha.-hydroxy-15-rippertene. Evidence for 1,2-methyl migration during biogenesis of a tetracyclic diterpene in termites

New diterpene isocyanides from a sponge

Six new diterpene isocyanides have been isolated from a sponge ( Adocia sp.). Their structures support the biosynthetic suggestion for the formation of diisocyanoadociane reported from the same sponge.

アセビPieris japonica葉の成分研究.新ジテルペンAsebotoxin-Xおよび新ジテルペン配糖体Pieroside Aの単離と構造決定

アセビPieris japonica葉の成分研究.新ジテルペンAsebotoxin-Xおよび新ジテルペン配糖体Pieroside Aの単離と構造決定

Presence of a tumor-promoting factor in honey.

Honey samples collected from the Saidabad area of Azarbaijan province of Iran were found to be moderately irritant, and this activity was associated with the presence of tri-acylates of the diterpene ingenol, which are transferred from the nectar of Euphorbia seguieriana Neck by honey bees to the honey. The acylates of ingenol are known promoters of carcinogenesis.

Aflavinine, a novel indole-mevalonate metabolite from tremorgen-producing [formula omitted][formula omitted] species

The structure of aflavanine, a new diterpene indole from A . flavus , is presented.

Diterpene composition of Cupressus dupreziana and Cupressus sempervirens

The heartwood of Cupressus dupreziana and C. sempervirens were shown to contain similar mixtures of diterpenes.

Neue diterpene aus der subtribus espeletiinae

The investigation of several species from the newly created subtribe Espeletiinae afforded in addition to known compounds seven new diterpenes and two norditerpenes. The structures were elucidated by intensive 1H-NMR studies. The chemotaxonomic situation is discussed briefly.

A new diterpene from the sponge [formula omitted][formula omitted

A new diterpene from the sponge [formula omitted][formula omitted

Inhibition of functional and morphological differentiation of cultured mouse myeloid leukemia cells by tumor promoters.

Addition of a potent tumor promoter, 12-O-tetradecanoylphorbol 13-acetate (TPA), to mouse myeloid leukemia line cells (Ml) in suspension cultures inhibited both functional and morphological differentiation of the cells induced by dexamethasone or protein inducer. A positive correlation was found between the tumor-promoting activities of several plant diterpenes and their inhibition of cell differentiation. The inhibition of cell differentiation by TPA was reversible and was unrelated to its cytotoxic action.

Strictic acid, a novel diterpene from Conyza stricta

Strictic acid, a novel diterpene from Conyza stricta

THREE ACETYLATED DITERPENE DIOLS OF VERRUCOSANE TYPE FROM THE LIVERWORT, Mylia verrucosa

Abstract Three new monoacetates of diterpene diols were isolated from Mylia verrucosa and the structures were determined as [2], [3] and [9] on the basis of chemical and spectral evidence.

New diterpenes from Sideritis sicula

Two new diterpenes have been isolated from Sideritis sicula: sideripol, ent-18-acetoxy-7α-hydroxykaur-15-ene and epoxysideritriol, ent-15β,16β-epoxykauran-7α,17,18-triol. The previously known diterpene eubol, ent-7α-acetoxykaur-16-en-15β,18 diol has also been obtained from the same source.