Three new diterpenoids from Coleus forskohlii Briq

Three new diterpenoids, forskolin G(2), forskolin H(3), forskolin I(4), were isolated from the whole plant of the Coleus forskohlii Briq., and their structures were elucidated as 1α,6β-diacetoxy-8,13-epoxylabd-14-en-11-one, 1α-hydroxy-6β,7β-diacetoxy-8,13-epoxylabd-14-en-11-one, and 1α,9α-dihydroxy-6β,7α-diacetoxy-8,13-epoxylabd-14-en-11-one on the basis of spectral data.     

Two new diterpenoids from Coleus forskohlii

Two new diterpenoids, forskolins I and J, have been isolated in our further investigation on Coleus forskohlii (Willd.) Briq. collected in Yunnan Province. Their structures have been determined as 1alpha,6beta-diacetoxy-7beta,9alpha-dihydroxy-8,13-epoxylabd-14-en-11-one (1) and 1alpha,9alpha-dihydroxy-6beta,7beta-diacetoxy-8,13-epoxylabd-14-en-11-one (2) by spectral methods (including 1D and 2D NMR techniques).     

Three new diterpenoids from Coleus forskohlii Briq

Three new diterpenoids, forskolin G(2), forskolin H(3), forskolin I(4), were isolated from the whole plant of the Coleus forskohlii Briq., and their structures were elucidated as 1alpha,6beta-diacetoxy-8,13-epoxylabd-14-en-11-one, 1alpha-hydroxy-6beta,7beta-diacetoxy-8,13-epoxylabd-14-en-11-one, and 1alpha,9alpha-dihydroxy-6beta,7alpha-diacetoxy-8,13-epoxylabd-14-en-11-one on the basis of spectral data.     

Three new cassane diterpenes from the seeds of Caesalpinia minax Hance

Three new cassane-diterpene-lactones, methyl 1α,7β-diacetoxy-5α,12α-dihydroxy-cass-13(15)-en-16,12-olide-17β-carboxylate (1), methyl 7β-acetoxy-1α,5α,12α-trihydroxy-cass-13(15)-en-16,12-olide-17β-carboxylate (2), and 12α-ethoxyl-1α,6α,7β-triacetoxy-5α,14β-dihydroxy-cass-13(15)-en-16,12-olide (3), were isolated from the seeds of Caesalpinia minax Hance. Their structures were established on the basis of HR-ESI-MS, 1D and 2D NMR spectral analysis.     

Feruhermonins A–C: three daucane esters from the seeds of Ferula hermonis (Apiaceae)

Seventeen daucane esters have been isolated from the seeds of Ferula hermonis Boiss (Apiaceae). Three of these sesquiterpenes, 4β-hydroxy-6α-benzoyl-7-daucen-9-one (1), 4β, 8β-dihydroxy-6α-benzoyl-dauc-9-ene (2), and 4β, 9α-dihydroxy-6α-benzoyl-dauc-7-ene (4), named feruhermonins A–C, respectively, are novel natural products. The structures of these compounds were elucidated unequivocally by a series of 1D and 2D NMR analyses. Although 4β, 8β-dihydroxy-6α-(4-hydroxy-3-methoxybenzoyl)-dauc-9-ene (3) was reported previously, the complete spectroscopic data for this compound are presented here for the first time.     

Three New Taxane Diterpenoids from the Seeds of the Chinese Yew,Taxus Chinensis var Mairei

Abstract

Three new taxoids were isolated from the seeds of the Chinese yew, Taxus chinensis var mairei, their structures were established as 9α,13α-diacetoxy-5α-cinnamoyloxy-11(15 → 1)-abeo-taxa-4(20), 11-diene-10β,15-diol, 2α,9α,10β-triacetoxy-taxa-4(20),11-diene-5α,13α-diol and 2α,7β,10β-triacetoxy-5α-cinnamyloxy-9α-hydroxy-taxa-4(20),11-diene-13-one on the basis of 1D, 2D NMR, and MS spectral analyses.     

Chemical constituents of Isodon nervosus and their cytotoxicity

Two new ent-kaurane diterpenoids, 6,20,15α-trihydroxy-6,7-seco-1α,7-olide-ent-kaur-16-ene (1) and 7β,12α-dihydroxy-6β,15β-diacetoxy-7α,20-epoxy-ent-kaur-2,16-dien-1-one (2), together with the six known compounds, were isolated from the aerial part of Isodon nervosus. The structures of the new compounds were determined by spectral methods (1D, 2D NMR, and MS). Six compounds were assayed for their cytotoxicity against HL60, SMMC-7721, and HeLa human cell lines. Compounds 5, 7, and 8 showed significant cytotoxicity.     

Two new sesquiterpene polyol esters from the root barks of Celastrus angulatus

Angulatin F (1) and angulatin I (2), two new sesquiterpene polyol esters, were isolated from the root barks of Celastrus angulatus, together with six known compounds 1β,2β-diacetoxy-4α,6α-dihydroxy-8α-isobutanoyloxy-9β-benzoyloxy-15-(α-methyl) butanoyloxy-β-dihydroagrofuran (3), angulatin A (4), angulatin B (5), celangulatin E (6), 1β,2β,15-triacetoxy-4α,6α-dihydroxy-8α-isobutanoyloxy-9β-benzoyloxy-β-dihydroagrofuran (7), and celangulin I (8). The structures of 1 and 2 were elucidated as 1β,2β,6α,15-tetraacetoxy-4α-hydroxy-8β,9α-difuroyloxy-β-dihydroagrofuran and 1β,2β,6α,8β,15-pentaacetoxy-4α-hydroxy-9β-furoyloxy-β-dihydroagrofuran by spectroscopic means.     

Two new cytotoxic ent-clerodane diterpenoids from Scutellaria barbata

Two new ent-clerodane diterpenoids have been isolated from Scutellaria barbata, and their structures were established by detailed spectroscopic analyses as (13R)-6α,7β-dihydroxy-8β,13-epoxy-11β-nicotinyloxy-ent-clerodan-3-en-15,16-olide (scutelinquanine D, 1) and (11E)-6α-acetoxy-7β,8β-dihydroxy-ent-clerodan-3,11,13-trien-15,16-olide (6-acetoxybarbatin C, 2). In vitro, the isolated two new compounds showed significant cytotoxic activities against three human cancer cell lines (HONE-1 nasopharyngeal, KB oral epidermoid carcinoma, and HT29 colorectal carcinoma cells), and gave IC₅₀ values in the range of 2.5–6.6 μM.     

Two new compounds from the fruiting bodies of Ganoderma philippii

Two new compounds, philippin (1) and 3β,9α,14α-trihydroxy-(22E,24R)-ergost-22-en-7-one (2), were isolated from the fruiting bodies of Ganoderma philippii. Their structures were elucidated on the basis of the spectroscopic technologies, including 1D and 2D NMR as well as MS. The bioassay of inhibitory activity against acetylcholinesterase (AChE) showed compound 1 exhibited weak inhibitory activity against AChE.     

Note: A new phytosterone from Achyranthes bidentata Bl.

A new phytosterone named achyranthesterone A (1), along with the three known compounds stachysterone D (2), β-ecdysone (3) and polypodine B (4) have been isolated from the roots of Achyranthes bidentata Bl. The structure of the new compound was determined as 2β,3β,14α,20S,21,22R,25-heptahydroxycholest-7-en-6-one on the basis of physico-chemical properties and spectral methods.     

Two new eremophilenolides from Ligularia lapathifolia

From the roots of Ligularia lapathifolia two new eremophilane-type sesquiterpenes have been isolated. Their structures were established as 3β-angeloyloxy-8β-hydroxy-6α,15β-epoxy-eremophil-7(11)-en-12,8α-olide (1) and 8βH-eremophil-3,7(11)-dien-12,8α (15,6α)-diolide (2) by spectroscopic methods including 2D NMR experiments.     

The sesquiterpenes from the roots of Cacalia roborowskii

A new sesquiterpene cacaroborin (1) was isolated from the roots of Cacalia roborowskii, together with three known ones, cinalbicol (2), isopetasin (3), and 3α-angeloyloxylactone (4). The structure of compound 1 was elucidated as 1β,10α-dihydroxy-8α-methoxyeremophil-7(11)-en-8β,12-olide on the basis of spectral evidence (1D, 2D NMR, IR, EI-MS, and HR-ESI-MS) and X-ray diffraction analysis.     

New eudesmane-type sesquiterpenoids from the root bark of Pseudolarix kaempferi

Abstract

The phytochemical investigation of the root bark of Pseudolarix kaempferi yielded eight eudesmane-type sesquiterpenoids, including three new ones, 1α-hydroxyl-4(14)-en-β-dihydroagarafuran (1), 1α, 2α-diacetoxy-8β-isobutanoyloxy-9α-benzoyl oxy-15-β-(β-furancarbonyloxy)-4β, 6β-dihydroxy-β-dihydroagarofuran (7), and 1α-acetoxy-2 α-furancarbonyloxy-8β-isobutanoyloxy-9α-benzoyloxy-15β-(β-acetoxy)-4β, 6β-dihydroxy-β-dihydroagarofuran (8). Herein the new compounds 7 and 8 were reported as a mixture. The molecular structures of the isolated compounds were elucidated on the basis of extensive spectroscopic analysis, including UV, IR, NMR, and MS, and comparison with the literature data.     

A new sesquiterpene ester from the fruits of Celastrus orbiculatus

From the fruits of Celastrus orbiculatus Thunb., a new dihydroagarofuran sesquiterpene ester named 6α,13β-diacetoxy-1β,8β,9β-tribenzoyloxy-β-dihydroagarofuran (1) has been isolated, along with three known compounds: 1β,6α,8β-triacetoxy-9α-benzoyloxy-β-agarofuran (2), 1β,6α-diacetoxy-9α-benzoyloxy-β-dihydroagarofuran (3) and β-sitostrol (4). The structure of 1 was elucidated on the basis of spectroscopic methods.     

Four new minor taxanes from cell cultures of Taxus chinensis

Four new minor taxanes (1–4) have been isolated from Ts-19 cell cultures of Taxus chinensis together with five known taxanes (5–9) by silica gel chromatography combined with semi-preparative HPLC chromatography. On the basis of the analyses of the chemical and spectroscopic (IR, MS, 1D, and 2D NMR) data, the structures of new compounds were elucidated as 5α-hydroxy-2α,10β-diacetoxy-14β-(3-hydroxy-2-methyl-butyryl)oxytaxa-4(20),11-diene (1), 2α,5α,10β-triacetoxy-14β-(2-hydroxy-propionyl)oxytaxa-4(20),11-diene (2), 2α,5α,10β-triacetoxy-14β-(2-hydroxy-3-methyl-butyryl)oxytaxa-4(20),11-diene (3), and 2α-benzoxy-4α,9α,10β,13α-tetraacetoxytax-11-ene (4), respectively. Compounds 1–5 were pharmacologically evaluated for their cytotoxicities against five human cancer cell lines (HCT-8, Bel-7402, BGC-823, A549, and A2780) and their reversing activity towards multi-drug resistance A549/taxol tumor cell line, and the results showed that all of the tested compounds exhibited very low cytotoxicities, while compound 4 possessed twice the reversing activity as that of verapamil at 10 μM.     

Microbial transformation of diosgenin by filamentous fungus Cunninghamella echinulata

Microbial transformation of diosgenin (1) by suspended-cell cultures of the filamentous fungus Cunninghamella echinulata CGMCC 3.2000 was investigated. Incubation of the substrate diosgenin (1) with this fungus led to the isolation of three products: two known compounds, (25R)-spirost-5-en-3β,7β,12β-triol (2) and (25R)-spirost-5-en-3β,7β,11α-triol (3), and a new compound (25R)-spirost-5-en-3β,7α,11α-triol (4). The structural elucidations of the three compounds were achieved mainly by the MS, 1D and 2D NMR spectroscopic methods and comparison with known compounds. C. echinulata CGMCC 3.2000 has not been used before in the biotransformation of diosgenin (1).     

Microbial transformation of oleanolic acid by Trichothecium roseum

Microbial transformation of the oleanolic acid (1) using Trichothecium roseum (pers.) Link (M 95.56) has resulted in the isolation of two new hydroxylated type metabolites, characterized as 15α-hydroxy-3-oxo-olean-12-en-28-oic acid (2) and 7β,15α-dihydroxy-3-oxo-olean-12-en-28-oic acid (3). The structure elucidation of these metabolites was based primarily on HR-EIMS, 1D NMR, and 2D NMR analyses.     

New triterpenes from Salacia hainanensis Chun et How with α-glucosidase inhibitory activity

Fractionation of the methanol extract from the roots of Salacia hainanensis Chun et How showing the potent inhibitory activity on α-glucosidase afforded two new lupane derivatives, 3α,28-dihydroxy-lup-20(29)-en-2-one (1) and 3α-hydroxy-lup-20(29)-en-2-one (2), a new friedelane derivative, D:A-friedo-oleanane-7α,30-dihydroxy-3-one (3), and a novel natural product, 2,3-seco-lup-20(29)-en-2,3-dioic acid (4), along with four known compounds (5–8). Their structures were established on the basis of spectral analysis, especially on the data afforded by 2D NMR and high-resolution mass spectra experiments. All of them showed a much stronger inhibiting activity on α-glucosidase than the positive control (acarbose, IC₅₀ = 5.83 μM). Constituents with α-glucosidase inhibitory activity from this plant are reported for the first time.     

A new meta-homoisoflavane from the fresh stems of dracaena cochinchinensis

A new meta-homoisoflavane, 10,11-dihydroxydracaenone C (1), together with 7,4′-dihydroxyflavone (2), 7,4′-dihydroxyflavane (3), 4,4′-dihydroxy-2-methoxychalcone (4), 4,4′-dihydroxy-2-methoxydihydrochalcone (5), 7,4′-dihydrohomoisoflavanone (6), 7,4′-homoisoflavane (7), lophenol (8), β-sitosterol (9), stigma-5, 22-diene-3-ol (10), 1-(4′-O-β-d-glucopyranosyl)benzyl-ethan-2-ol (11), 3,4-dihydoxy-1-allylbenezene-4-O-α-l-rhamnopyranosyl-(1 → 6)-O-β-d-glucopyranoside (12), 1-hydroxy-3,4,5-trimethoxybenzene-1-O-α-l-apiopyranosyl-(1 → 6)-O-β-d-glucopyranoside (13), and tachioside (14) have been isolated from the fresh stems of Dracaena cochinchinensis. Their structures have been established by spectroscopic analysis, especially by 2D NMR. This is the first time compounds 11, 13, 14 have been isolated from Dracaena.