(+)-Arctigenin,a lignan from Wikstroemia indica

A new lignan, (+)-aretigenin has been isolated from the roots of Wikstroemia indica (Nan-Ling-Jao-Hua) and identified as 8(R) 8′(S)-4′-hydroxy-3, 4,3′-trimethoxylignan-olid (9, 9′) on the basis of spectral evidence as well as a direct comparison with its enantiomer, (?)-arctigenin.     

Geniculatin,a triterpenoid saponin from Euphorbia geniculata

A new triterpenoid saponin, geniculatin, has been isolated from the ethanolic extract of Euphorbia geniculata (Euphorbiaceae). The saponin has been identified as 3β-[L-rhamnopyranosyl-(1→4)-D-xylopyranosyl-(1→4)-D-β-glucoronopyranosyl-(1→3)]-oxyolean-12-en-28-oic acid.     

(+)-Calocedrin,a lignan dihydroanhydride from Calocedrus formosana

A novel lignan dihydroanhydride, (+)-calocedrin, was isolated from the wood of Calocedrus formosana. Its structure was determined to be trans-α-(3,4-methylenedioxybenzylidene)-β-(3,4-methylenedioxybenzyl)-γ-hydroxybutanolide by spectroscopic methods. Reduction of (+)-calocedrin resulted in an optically inactive lignan lactone, (±)-hibalactone.     

A lignan glucoside from Euphrasia rostkoviana

A new lignan glucoside has been isolated from Euphrasia rostkoviana. Its structure was elucidated by spectroscopic means and by correlation with dehydrodiconiferyl alcohol to be dehydrodiconiferyl alcohol- 4-β-d-glucoside.     

Prinsepiol,a lignan from stems of Prinsepia utilis

Chemical investigation of Prinsepia utilis yielded a new lignan designated prinsepiol, in addition to l-epicatechin and β-sitosteryl-β-glucoside. Prinsepiol was shown to be 1,5 - dihydroxy - 2,6 - di(4′ - hydroxy - 3′ - methoxyphenyl) - 3,7 - dioxabicyclo[3,3,o]octane, on the basis of spectral and other evidence.     

(+)-Tsugacetal,a lignan acetal from Taiwan hemlock

By the evidence of ¹H and ¹³C NMR spectra, and single crystal structure determination, a novel lignan acetal, (+)-tsugacetal, isolated from Tsuga chinensis var. formosana, was found to have an α-conidendrin-related structure with an acetal methoxy group at the β-position.     

Poilaneic acid,a cembranoid diterpene from Croton poilanei

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

(−)-di-de-o-methylgrandisin, a lignan from Virola pavonis leaves

Leaves of Virola pavonis yielded a (7,7′β,8β,8′)-4,4′-dihydroxy-3,3′5,5′-tetramethoxy-7,7′-epoxyligna (−)-di-de-O-methylgrandisin.     

A naphthoquinone and a lignan from the wood of Kigelia pinnata

A new naphthoquinone, kigelinone, and a new lignan, kigeliol, together with six known constituents including lapachol and dehydro-α- lapachone, were isolated from the wood of Kigelia pinnata. On the basis of spectral data and chemical degradations, kigelinone was characterized as 2-(1-hydroxyethyl)-8-hydroxy-naphtho[2,3-b]furano-4,9-dione and kigeliol as (2S,6S)-bis(3,4-methylenedioxyphenyl)- 3,7- dioxabicyclo[3.3.0]octan-1R,5R-diol or its enantiomer.     

Glutathione s-transferase from hevea brasiliensis

Glutathione (GSH) S-transferase can be detected in a variety of tissues of Hevea brasiliensis. Lyophilized powders prepared from 20 000 g supernatants of latex adjusted to pH 5.0 contain substantial amounts of GSH S-transferase activity which is stable at ? 20° for up to 6 months. The enzyme has a broad pH optimum between 8.5 and 9.5. The K_m values for GSH and 1-chloro-2,4-dinitrobenzene are in the range of 33–45 and 150–200,μM, respectively. The enzyme has a MW in the range of 47 000–50 000 and an isoelectic point of 4.3. Although it appears homogeneous on analytical polyacylamide disc gel electrophoresis (PAGE) and isoelectric focusing, it resolves into five forms on DEAE-Sephadex chromatography.     

苍白秤钩风(Diploclisia Glaucescens)中的木脂素——左旋丁香脂素的晶体结构研究

通过X 射线单晶衍射法测定了标题化合物的晶体结构。结果表明 :晶体属正交晶系 ,P2 12 12 1空间群 ,a =8 6 0 10 (3) ,b =13 0 830 (9) ,c =18 1130 (11) ,V =2 0 38 2 0 (2 0 ) 3 ,Z =4 ,Mr =4 18 4 9,Dx =1 36 9g/cm3 ,λ(MoKα) =0 710 73 ,μ(MoKα) =1 12cm-1,F(0 0 0 ) =888。在 0 <2θ <5 0°范围内共收集了 1988个独立衍射点 ,其中可观测衍射点 196 3个 [Ⅰ≥ 8σ(Ⅰ ) ]。晶体结构用直接法解出 ,经全矩阵最小二乘法修正 ,最终偏离因子Rf=0 0 6 2 ,Rw=0 0 5 5。     

A diterpene from Euphorbia maddeni

From the anticancer-active CHCl₃, extract of the plant Euphorbia maddeni, a polyacylated diterpene of jatrophone type, euphornin, has been isolated and its structure elucidated by physico-chemical methods.     

Mallotin—a new C32 triterpenoid from Mallotous stenanthus

Mallotin, a new C₃₂ triterpene from Mallotous stenanthus, has been isolated and its structure established as 24,24-dimethyl-lanosta-7,25-dien-3α-ol.     

Structure of a secoisolariciresinol diester from Salvia plebeia seed

The structure of a unique lignan diester from Salvia plebeia seed has been determined. Hydrolysis of the diester yields ferulic acid, (+)-l2 l-methyltetradecanoic acid and secoisolariciresinol.     

New hydroxy fatty acid from seed oil of Baliospermum axillare

A fatty acid, found as a minor component in the seed oil of Baliospermum axillare, is shown to be the hitherto unknown 11,13-dihydroxytetracos-trans-9-enoic acid (axillarenic acid).     

Tumour-inhibitory aryltetralin lignans from Podophyllum pleianthum

Roots of Podophyllum pleianthum contain eight aryltetralin lignans: podophyllotoxin, desoxypodophyllotoxin, podophyllotoxone, isopicropodophyllone and the four corresponding 4′-demethyl derivatives. The lignan pattern is very similar to that of P. hexandrum. A useful TLC spray reagent for Podophyllum lignans is described.