Carbon-13 Nuclear Magnetic Resonance Spectra of Some Protoilludane Sesquiterpenoid Aromatic Esters from Armillaria mellea (Vahl.ex Fr.) Quel.

The carbon-13 nuclear magnetic resonance spectra of seventeen protoilludane ses- quiterpenoid aromatic esters from the artificially cultured mycelium of Armillaria mellea (Vahl.ex Fr.) Quel.have been analysed and assigned.All the ^(11)CNMR signals of the model compounds melleolide 5 and compounds 8,10,11,13,14,15,and 16 can be assigned on the basis of the multiplicity of the sig- nals in the off-resonance decoupled spectra or INEPT spectra.^(11)C-~1H COSY and long-range ^(13)C-~1H COSY.The assignments of the ^(13)CNMR spectra of other protoilludane sesquiterpenoid aromatic esters were completed by comparison with the model compounds as well as the electronic effects of substi- tuted group on the molecules.The present results indicate that ^(11)CNMR spectroscopy provides an ef- fective method for characterizing the protoilludane sesquiterpenoid aromatic esters.

A New Sesquiterpenoid from Russula lepida

new aristolane sesquiterpenoid named rulepidol was isolated from the fruiting body of Russula lepida Fr. Its structure was elucidated as (1a alpha ,5 alpha ,7 alpha ,7a alpha, 7b alpha)-1, 1a,4,5,6,7,7a, 7b-octahydro-5-hydroxy-1,1,7,7a-tetramethyl-5H-cyclopropa [alpha] naphthalen-2-one mainly by 1D and 2D-NMR techniques.

Eremophilane Sesquiterpenoids from Coleus xanthanthus

A new eremophilane sesquiterpenoid, along with two known ones, was isolated from the ethyl acetate soluble fraction of the aerial part of Coleus xanthanthus C. Y. Wu et Y. C. Huang. Their structures were elucidated as 4,5,11_trimethyl_8,9_seco_1(10),7(11)_eremophiladien_8,12_olid_9_oic acid (1), 2,9_dioxoeuryopsin (2) and 9_oxoeuryopsin (3) by spectral methods. The 1H_NMR and 13 C NMR data of compounds 1, 2 and 3 were unambiguously assigned on the basis of two_dimensional NMR spectroscopy.

THE STRUCTURE OF ARMILLARIZIN,A NEW PROTOILLUDANE SESQUITERPENOID AROMATIC ESTER FROM ARMILLARIA MELLEA(VAHL.EX FR)QUEL.

A new protoilludane sesquiterpenoid aromatic ester,named armillarizin (1)has been isolated from the artificially cultured mycelium of Armillaria me- llea(Vahl.ex Fr)Quel.(Tricholomataceae).Its structure was deduced on the ba- sis of spectral analyses.The relative configuration was established from the nuclear Overhauser effects and from the values of ~1H-~1H coupling constants.

New Sesquiterpenoids from Hedychium yunnanense gagnep

Two new sesquiterpenoid trialcohol isomers named 1 beta, 4 alpha 11 alpha -trihydroxyeudesmane (1) and Yunnanensehedychetriol (2), were isolated from the fresh rhizomes of Hedychium Yunnanense gagnep. Their structures were elucidated by spectroscopic methods.

Two novel fomannosane-type sesquiterpenoids from the culture of the basidiomycete Agrocybe salicacola

Two novel fomannosane-type sesquiterpenoids,agrocybins H(1)and I(2),together with a known compound illudosin(3),were isolated from the culture broth of the mushroom Agrocybe salicacola.Their structures were elucidated by extensive spectroscopic analysis.The relative stereochemistry of 1 was determined by the use of single crystal X-ray crystallographic diffraction.

Drimane Sesquiterpenoids and Isochromone Derivative from the Endophytic Fungus Pestalotiopsis sp. M-23

Three new drimane sesquiterpenoids(1–3)together with the known 2a-hydroxyisodrimeninol(4),and a new isochromone derivative(5),were obtained from the solid cultures of fungal strain Pestalotiopsis sp.M-23,an endophytic fungus isolated from the leaves of Leucosceptrum canum(Labiatae).Their structures were determined by comprehensive 1D and 2D NMR,and MS analyses.The metabolites were evaluated for their antibacterial activities,and compound 3 showed weak inhibitory activity against Bacillus subtilis.

Sesquiterpenoids and 2-(2-Phenylethyl)chromone Derivatives from the Resinous Heartwood of Aquilaria sinensis

One novel spirolactone,aquilarisinolide(1),three new sesquiterpenoids,(2R,4S,5R,7R)-2-hydroxyeremophila-9,11-dien-8-one(2),(1R,4S,5S,7R,11R)-13-hydroxyepidaphnauran-9-en-8-one(3),and(4R,5S,7R,8S,10S,13R)-8,13-dihydroxyrotunda-1,11-dien-3-one(4),together with 13 known compounds(5-17)were isolated from the resinous heartwood of Aquilaria sinensis(Thymelaeaceae).The structures of the new compounds were elucidated based on the analysis of NMR and MS data and theoretical calculations their ECD spectra.The isolated compounds were evaluated for their protective activities against PC12 cell injury induced by corticosterone(CORT)and 1-methyl-4-phenylpyridine ion(MPP+),as well as inhibitory activities against BACE1.Compound 4,5,6-dihydroxy-2-(2-phenylethyl)chromone(5),daphnauranol B(7),6-methoxy-2-[2-(3-methyoxyphenyl)ethyl]chromone(10),isoagarotetrol(14),and 1-hydroxy-1,5-diphenylpentan-3-one(16)showed significant protective effects on CORT-induced injury in PC12 cells at a concentration of 20μM(P<0.001).Isoagarotetrol(14)showed a significant protective effect on MPP+-induced injury in PC12 cells at a concentration of 20μM(P<0.001),while compound 4 showed a moderate activity(P<0.01).The BACE1-inhibitory activities of all tested compounds were very weak with less than 30%inhibition at a concentration of 20μM.

Two New Eudesmane Sesquiterpenoids from the Flowers of Chrysanthemum indicum

The fowers of Chrysanthemum indicum,i.e.Ye-ju-hua recorded in the Chinese Pharmacopoeia,has been widely used in China as an important heat-clearing and detoxifying herb for the treatment of infammation,headache,and vertigo.A phytochemical investigation of this herb has led to the isolation of two new eudesmane sesquiterpenoids,7-epi-eudesm4(15),11(13)-diene-1β,3β-diol(1)and 7-epi-1β-hydroxy-β-eudesmol(2).The molecular structures of these new sesquiterpenoids were established based on the comprehensive spectroscopic analyses,including NMR,MS,and IR,and comparing with the literatures.

Sesquiterpenoids from the Rhizomes of Homalomena occulta

Naturally occurring oplopanane sesquiterpenoids are rarely reported.A phytochemical investigation on the rhizomes of Homalomena occulta(Lours)has resulted in the discovery of six oplopanane sesquiterpenoids(1–6),including four new(1–4)and one 3,5-seco-oplopanane(6),together with three previously reported sesquiterpenoids(7-9).In addition three new oplopananes(2a–4a)were also obtained by chemical transformation.All structures of these sesquiterpenoids were established based on the comprehensive spectroscopic analyses,including NMR,MS,and IR,and comparing with the literatures.

A New Sesquiterpenoid from Magnolia delavayi

A new sesquiterpenoid was obstained from the leaves of Magnolia delavayi. Its structure was determined as 8β-acetoxy-10α-ethyloxy-guaia-4α, 11-diol on the basis of spectral evidence.

Drimane sesquiterpenoids from a wetland soil-derived fungus Aspergillus calidoustus TJ403-EL05

Soil-derived fungi represent an insufficiently tapped reservoir for discovering new and bioactive natural products(NPs),and despite an ever-increasing number of unknown NPs have been discovered over the past few decades,much of the hidden biosynthetic potential is still in an urgent need to be disclosed.In this research,a chemical inves-tigation was performed on a wetland soil-derived fungus Aspergillus calidoustus TJ403-EL05,leading to the isolation of a total of fourteen drimane sesquiterpenoids(1-14),incorporating three new ones,namely ustusols F-H(1-3).Their structures,comprising absolute configurations,were completely authenticated by widespread spectroscopic data,quantum chemical 13C NMR and ECD calculations,and X-ray crystallography experiments.Compound 14 exhibited moderate anti-inflammatory activity by inhibiting the LPS-induced NO release(IC_(50)=25.6μM).

Two Eremophilane-type Sesquiterpenoids from the Rhizomes of Ligularia veitchiana(Hemsl.) Greenm

Two eremophilane-type sesquiterpenoids from the rhizomes of Ligularia veitchiana（Hemsl.） Greenm were isolated and determined as 10α,11-endoperoxide-1（2）-en-7α-hydroeremophilane（1） and 1（10）-en-2-oxo-7α-isopropanol-eremophilane（2）.Compound 1 was a new compound and compound 2 was a new natural product.The structures of the two compounds were established by means of spectral methods including 1^H NMR,13^C NMR,2D NMR and MS.

Non-isoprenoid botryane sesquiterpenoids from basidiomycete Boletus edulis and their cytotoxic activity

Three non-isoprenoid botryane sesquiterpenoids,named boledulins A-C(1-3),have been isolated from the cultures of basidiomycete Boletus edulis Bull.The structures were established by means of spectroscopic methods.Boledulin A(1)exhibited moderate inhibitory activity against five human cancer cell lines.

Dendrowardol C, a novel sesquiterpenoid from Dendrobium wardianum Warner

Dendrowardol C(1)-a novel sesquiterpenoid,with an unprecedented 4/5/6/6 tetracyclic carbon backbone,together with two known cyclopacamphane-type sesquiterpenoids;dendronobilin I(2)and dendrobane A(3)were isolated from the stems of Dendrobium wardianum Warner.The structure of 1 was established on the basis of spectroscopic data and the absolute configuration was determined by single-crystal X-ray diffraction crystallography.The hypothetical biosynthetic pathway of 1 was postulated.Compound 1 showed no cytotoxic activity against human tumor cell lines HL-60,SMMC-7721,A-549,MCF-7,and SW480.

A comprehensive review on the chemical constituents,sesquiterpenoid biosynthesis and biological activities of Sarcandra glabra

Sarcandra glabra(Thunb.)Nakai is a perennial evergreen herb categorised within the Sarcandra Gardner genus under the Chloranthaceae family.Indigenous to tropical and subtropical regions of East Asia and India,this species is extensively distributed across China,particularly in the southern regions(Sichuan,Yunnan,and Jiangxi).In addition to its high ornamental value,S.glabra has a rich history of use in traditional Chinese medicine,evident through its empirical prescriptions for various ailments like pneumonia,dysentery,fractures,bruises,numbness,amenorrhea,rheumatism,and other diseases.Besides,modern pharmacological studies have revealed various biological activities,such as antitumour,anti-bacterial,anti-viral anti-inflammatory and immunomodulatory effects.The diverse chemical constituents of S.glabra have fascinated natural product researchers since the 1900s.To date,over 400 compounds including terpenoids,coumarins,lignans,flavonoids,sterols,anthraquinones,organic acids,and organic esters have been isolated and characterised,some featuring unprecedented structures.This review comprehensively examines the current understanding of S.glabra’s phytochemistry and pharmacology,with emphasis on the chemistry and biosynthesis of its unique chemotaxonomic marker,the lindenane-type sesquiterpenoids.

A New Antimalarial Noreudesmane Sesquiterpenoid from Dobinea delavayi

One previously undescribed angeloylated noreudesmane sesquiterpenoid,dobinin O(1),along with four known eudesmane sesquiterpenoids(2-5)were isolated from the peeled roots of Dobinea delavayi.Their structures were elucidated by extensive spectroscopic data analyses.In addition,compound 1 exhibited moderate antimalarial activity against Plasmodium yoelii BY265RFP with the inhibition ratio of 17.8±13.3%at the dose of 30 mg/kg/day.

New Azulene-Type Sesquiterpenoids from the Fruiting Bodies of Lactarius deliciosus

In the^(1)H NMR-guided fractionation of extracts from the edible mushroom Lactarius deliciosus,two new azulene-type sesquiterpenoids,7-isopropenyl-4-methyl-azulene-1-carboxylic acid(1)and 15-hydroxy-3,6-dihydrolactarazulene(2),together with seven known compounds were characterized.Their structures were determined on basis of spectroscopic evidence,as well as by comparing with literature data.Amongst the known metabolites,the^(13)C NMR assignment of 15-hydroxy-6,7-dihydrolactarazulene(3)is reported here for the first time.Moreover,7-acetyl-4-methylazulene-1-carbaldehyde(5)displayed a moderate antibacterial activity against Staphylococcus aureus.

Seco-sativene and Seco-longifolene Sesquiterpenoids from Cultures of Endophytic Fungus Bipolaris eleusines

Two new seco-sativene sesquiterpenoids,bipolenins D(1)and E(2),a new seco-longifolene sesquiterpenoid,bipolenin F(3),together with three known analogues(4–6),were obtained from cultures of endophytic fungus Bipolaris eleusines.Their structures were established by MS and NMR data.Compounds 1–6 showed no activity to five human cancer cell lines.

Cytosporinols A-C,new caryophyllene sesquiterpenoids from Cytospora sp.

Three new caryophyllene sesquiterpenoids,cytosporinols A-C(1-3),have been isolated from solid cultures of Cytospora sp.The structures of 1-3 were elucidated primarily by NMR spectroscopy,and 3 was further confirmed by X-ray crystallography.The absolute configurations of the C-11 secondary alcohol in 1 and the 6,8-diol moiety in 3 were deduced using the modified Mosher and Snatzke’s method,respectively.Compounds 2 and 3 showed moderate cytotoxicity against HeLa cells.