A new ent-kaurane diterpenoid from Isodon japonica

<正>One new ent-kaurane diterpenoid,named maoyecrystal L was isolated from the EtOAc extract of the dried leaves of lsodon japonica.Its structure was established by various spectroscopic means and confirmed by X-ray crystallographic analysis.     

Antibacterial Constituents from Isodon Excisoides

Two new ent‐kaurane diterpenoids, taihangexcisoidesin C (1) and its acetonide, taihangexcisoidesin D (2), along with 9 known compounds were isolated from the leaves of Isodon excisoides. The structures of the new compounds were elucidated using 1D and 2D NMR spectroscopy analysis. Compounds 3‐6 and 8‐9 were tested for their antibacterial activity against Escherichia coli, Staphylococcus aureus, S. epidermidis and S. saprophyticus. Compound 6 showed inhibitory effects on Staphylococcus aureus, S. epidermidis and S. saprophyticus MIC values 32, 16 and 16 μg/mL, respectively. All of the compounds didn't show effects on Escherichia coli (MIC > 10 mg/mL).     

Two new ent-kaurane diterpenoids from Isodon henryi

Two new ent-kaurane diterpenoids, minheryins H （1） and I （2）, were isolated from the leaves of Isodon henryi. Their structures were elucidated by means of spectroscopic analysis, including 2D NMR spectra.     

Two new diterpenoids from Isodon serra

From the aerial part of Isodon serra,two new ent-6,7-seco-kaurane-type diterpenoids,15α,20β-dihydroxy-6β-methoxy-6,7- seco-6,20-epoxy-1,7-olide-ent-kaur-16-ene (1) and 6α,15α-dilaydroxy-20-aldehyde-6,7-seco-6,11α-epoxy-1,7-olide-ent-kaur-16- ene (2) were isolated.Their structures were elucidated by spectroscopic means.     

Novel ent ‐Kaurane Diterpenoids from Isodon xerophilus

Further investigation on the leaves of Isodon xerophilus afforded three novel ent‐kaurane diterpenoids, xerophilusins D‐F (1–3), together with seven known compounds, phyllostachysin A (4), oleanolic acid, caffeic acid, rosmarinic acid, rutin, quercetin‐3‐O‐β‐D‐glucopyranoside, and quercetin. Structures of 1–3 were elucidated on the basis of their spectral properties and X‐ray crystallographic analysis. Compound 1 showed broad spectra inhibiting human tumor cells and significant cytotoxicity.     

Negative electrospray ionization tandem mass spectrometric investigation of ent-kaurane diterpenoids from the genus Isodon

ent-Kaurane diterpenoids are a class of natural compounds isolated from genus Isodon, which have been found to have important bioactivities. Negative electrospray ionization tandem mass spectrometry ((-)ESI-MS(n)) was used to investigate the fragmentation pattern of C-20-nonoxygenated ent-kauranes and two subtypes of C-20-oxygenated ent-kauranes by using an ion trap instrument and accurate mass measurement on an ESI-Q-time-of-flight (TOF) mass spectrometer. The analysis revealed that loss of CH(2)O or CO(2) is the predominant process for 7, 20-epoxy and 7, 20 : 14, 20-diepoxy subgroup of C-20-oxygenated ent-kauranes. In addition, compounds of C-20-nonoxygenated ent-kauranes with a conserved core structure but different substituent groups, such as a hydroxyl, aldehyde, carboxyl, and acetyl moiety, resulted in diagnostic product ions through losses of H(2)O, CO, CO(2), and AcOH, respectively. This work clearly demonstrates the utility of tandem mass spectrometry for studies on the rationalization of the diagnostic fragmentation of a series of compounds from two main types of the ent-kaurane diterpenoids.     

Two new 19-oxygenated ent-kaurane diterpenoids from Isodon pharicus

<正>Two new 19-oxygenated ent-kaurane diterpenoids,pharicinins D and E(1 and 2),together with an artifact,pharicinin D acetal (3) were isolated from the leaves of Isodon pharicus.Their structures were determined by 1D and 2D NMR spectroscopic analysis. All of them were evaluated for their cytotoxicity.     

New ent-kaurane-type diterpenoids from Isodon nervosus

Two new ent-kaurane-type diterpenoids,6β,7β,13α-trihydroxy-1α-acetoxy-7α,20-epoxy-ent-kaur-16-en-15-one（1）and 15β- hydroxy-6,7-seco-6,11β：6,20-diepoxy-1α,7-olide-ent-kaur-16-ene（2）were isolated from the Isodon nervosus,and the structures were elucidated by spectroscopic analysis.     

A New ent-Kaurane Diterpenoid from Isodon enanderianus

Isodon enanderianus (Hand. -Mazz.) H. W. Li, has been used in folk medicine as anti-inflammatory and detoxified agent1. The Isodon genus is known to be rich in ent-kaurane diterpenoids, a series of new ent-kaurane diterpenoids have been isolated from the dried leaves of I. enanderianus2-4. In order to find more biologically active substances, we have carefully investigated the chemical constituents of I. enanderianus collected in Shiping county of Yunnan province, and as a result, enanderi…     

Two New Diterpenoids and other Constituents from Isodon Nervosus

Two new ent‐kaurane diterpenoids, 15β‐hydroxy‐6,7‐seco‐6,11β:6,20‐diepoxy‐1α,7‐olide‐ent‐kaur‐16‐ene ( 1 ), 11α,15α‐dihydroxy‐6β‐methoxy‐6,7‐seco‐6,20‐epoxy‐1α,7‐olide‐ent‐kaur‐16‐ene ( 2 ), together with four known diterpenoids, nodosin ( 3 ), isodocarpin ( 4 ), odonicin ( 5 ) and maoyecrystal F ( 6 ) were isolated from the aerial parts of Isodon nervosus. The structures of the new compounds were elucidated on the basis of their spectral evidence, especially on 2D NMR.     

Two new ent-kaurane diteroenoids from Isodon excisoides

Two new ent-kaurane diterpenoids taihangexcisoidesin A and B(1 and 2),were isolated from the EtOAc extract of the leaves of Isodon excisoides.Their structures were determined on the basis of spectroscopic methods.     

A new ent-abietane diterpenoid from Isodon macrophyllus

A new ent-abietane diterpenoid, named dayecrystal C, was isolated from the EtOAc extract of the dried leaves of Isodon macrophyllus. Its structure was determined on the basis of spectroscopic methods.     

A new ent-labdane diterpenoid from Andrographis paniculata

<正>A new ent-labdane diterpenoid,19-O-β-D-glucopyranosyl-ent-labda-8(17),13-dien-15,16,19-triol,together with six known ent-labdane diterpenoids,was isolated from the aerial parts of Andrographis paniculaia.The structure of the new compound was elucidated by extensive spectral analysis.     

A new ent-kaurane diterpenoid from Ixora amplexicaulis

A new ent-kaurane diterpenoid, 6α,16α-dihyroxy-ent-kaurane (1), was isolated from the stems of Ixora amplexicaulis, together with (24R)-6β-hydroxy-24-ethyl-cholest-4-en-3-one (2), 7β-hydroxysitosterol (3), maslinic acid (4), 3,3′-bis(3,4-dihydro-4-hydroxy-6-methoxy-2H-1-benzopyran) (5) and protocatechuric acid (6). Their structures were established by extensive spectroscopic analysis, including 2D NMR techniques. Compounds 2–5 were isolated from the genus Ixora for the first time and 6 obtained originally from I. amplexicaulis.     

贵州冬凌草的对映－贝壳杉烷二萜化合物

从贵州产冬凌草[Isodon rubescens (Hemsl.) Hera]中分离得到12个6，7－断 裂－7，20－内酯－对映－贝壳杉烷二萜化合物，经波谱分析鉴定了它们的结构， 其中有7个新化合物，分别命名为贵州冬凌草乙素～辛素（guidongnins B～H, 1～ 7)，以及卢氏冬凌草甲素（8）、卢氏冬凌草乙素（9）、贵州冬凌草素（10）、狭 叶香茶菜素(angustifolin, 11)和6－表香茶菜素（6-epiangustifolin, 12)等5个 已知化合物。另外，将作者原命名的贵州冬凌草素（guidongnin, 10）更名为贵州 冬凌草甲素(guidongnin A, 10)，并利用二维核磁区振波谱技术修订了卢氏冬凌草 乙素的结构。     

A New 6,7-Seco-Ent-Kaurane Diterpenoid from Isodon eriocalyx Var. laxiflora

Isodon eriocalyx var. laxiflora C. Y. Wu & H. W. Li, is a perennial herb naturally growing in the southern area of Yunnan province. In our continuing studies1 on its leaves collected from Xishuanbana prefecture, a new 6,7-seco-ent-kaurane diterpenoid, named laxiflorin E (1), together with two known 6,7-seco-ent-kaurane diterpenoids2, eriocalyxin A (2) and laxiflorin C (3), was isolated. Their structures were established by spectroscopic analysis. Compound 1, obtained as colorless rhombus…     

A new ent-labdane diterpenoid lactone from Andrographis paniculata

<正>A new ent-labdane diterpenoid lactone was isolated from Andrographis paniculata.Its structure was identified on the basis of spectral data including 2D NMR.     

Two Novel Sub-skeleton Types of ent-Kauranoids from Isodon gesneroides

Two novel ent-kauranoids with new sub-skeleton types, gesneroidins G and H were isolated as white powder from the ether extract of the leaves of Isodon gesneroides through normal phase column chromatography. Their structures were elucidated as 3β,6α,7β-triacetoxyl-15-hydroxyl-14-oxo-ent- 15,16-seco-kaur-11,17-olide and Iα-hydroxyl-3β,6α,7β,11 β-tetraacetoxyl-ent-nor-15,17-kaur-8,16-olide on the basis of the spectral evidences including ID and 2D NMR spectra.     

A new phenylethanoid glycoside from Isodon sculponeatus

A new phenylethanoid glycoside,seulponisidc(1) was isolated from the aerial parts of Isodon sculponeatus(Vaniot) Kudo, along with six known compounds martynoside(2),verbascoside(3),(+)-hydroxypinoresinol-8-O- β-D-glucoside(4),cedrusin(5), 7-megastigmene-3S,5R,6R,7E,9S-tetrol(6) and 4-oxo- β-ionol- β-D-glucopyranoside(7).Their chemical structures were elucidated from physieochemical data and by acidic hydrolysis.     

A new diterpenoid alkaloid from Aconitum hemsleyanum

Abstract

A new C₁₉-diterpenoid alkaloid named hemsleyaline (1), along with fourteen known alkaloids (2-15), were isolated from the roots of Aconitum hemsleyanum Pritz. (Ranunculaceae), a herbal medicine in southwest China. Their structures were established on the basis of extensive spectroscopic analyses. Compound 1 showed mild cholinesterase inhibitory effect with IC₅₀ value of 471?±?9?μM.