New sesquiterpenes from Capsicum annuum

The ethyl acetate soluble fraction of a MeOH extract of the dried stems and roots of Capsicum annum gave 10 new sesquiterpenoids (1-10) and nine known compounds. The structures of the new compounds were elucidated on the basis of spectroscopic evidence. The isolated new compounds were evaluated for their cytotoxic activities.     

Chemical constituents from the Colombian medicinal plant Maytenus laevis

The methanol extract of the bark of the Colombian medicinal plant Maytenus laevis gave six new compounds and 28 known compounds. The structures of the new and known compounds were elucidated on the basis of spectroscopic evidence. Several of these compounds were screened for cytokine-inducing activity on human PBMCs to investigate antitumor effects, and canophyllol (12) demonstrated the most effective induction of the cytokines.     

Acetylated sesterterpenes from the Great Barrier Reef sponge Luffariella variabilis

Chemical investigation of the sponge Luffariella variabilis collected from the Palm Island group of the Great Barrier Reef, Australia, yielded three new acetylated compounds, 25-acetoxyluffariellin A (1), 25-acetoxyluffariellin B (2), and 25-acetoxyseco-manoalide (3). The structures of the new compounds were elucidated on the basis of interpretation of their spectroscopic data. The known metabolites manoalide (4), seco-manoalide (5), luffariellin A (8), and manoalide monoacetate (10) were also isolated. The new acetylated compounds (1-3) were labile in the sponge tissue when samples were allowed to thaw prior to extraction, but were stable once isolated. Sponge samples that were completely thawed contained only hydroxylated compounds (alcohols). This finding supported the deduction that the acetylated compounds are being enzymatically transformed and/or degraded.     

2003年我国天然药物化学研究进展

检索国内外药学核心期刊，按照结构类型对2003年发现的新化合物进行综述，并对具有生物活性的化合物进行了重点介绍。2003年我国学者共发表文章400多篇，分离鉴定化合物2200多个，其中新化合物604个．活性化合物64个。通过对新化合物的归纳整理及生物活性的介绍，为新药的研究与开发提供参考。     

Diterpenes, sesquiterpenes, and a C15-acetogenin from the marine red alga Laurencia mariannensis

In addition to 10 known compounds (7- 16), one new brominated diterpene, 10-hydroxykahukuene B (1), two new sesquiterpenes, 9-deoxyelatol (2) and isodactyloxene A (3), one new brominated C 15-acetogenin, laurenmariallene (4), and two new naturally occurring halogenated sesquiterpenes (5 and 6) that were previously obtained as intermediates in a biomimetic synthetic study of rhodolaureol and rhodolauradiol have been isolated and identified from the organic extract of the marine red alga Laurencia mariannensis. The structures of these compounds were established by spectroscopic methods. The antibacterial and antifungal activities of new compounds 1-4 were evaluated.     

Antileishmanial compounds from Cordia fragrantissima collected in Burma (Myanmar)

A methanol extract of the wood of Cordia fragrantissima, collected in Burma (Myanmar), was found to exhibit significant activity against Leishmania major. Bioassay-guided fractionation of this extract using several chromatographic techniques afforded three new compounds (1-3) and five known compounds (4-8). The structures of the new compounds were revealed on the basis of spectroscopic data interpretation and by X-ray crystallographic analysis. Interestingly, the new compounds, despite the presence of asymmetric carbons, were found to be racemates. The activities of the isolates from C. fragrantissima and several derivatives were evaluated against the promastigote forms of Leishmania major, L. panamensis, and L. guyanensis.     

Alpha-glucosidase inhibitory anthranols, kenganthranols A-C, from the stem bark of Harungana madagascariensis

One new prenylated 1,4-anthraquinone and three new prenylated anthranols, named kengaquinone (1) and kenganthranols A (2), B (3), and C (4), were isolated from a hexane extract of the stem bark of Harungana madagascariensis. Six known compounds including anthraquinones, anthrones, and xanthones were also isolated and identified. The structures of the new compounds were determined by analysis of spectroscopic data and comparison with data of previously known analogues. Some isolated compounds (3-5, 7-11) were evaluated for their alpha-glucosidase inhibition activity. Compounds 3, 4, 8, and 11 showed significant activity, whereas compounds 7, 9, and 10 were inactive in this test.     

New flavones from Millettia erythrocalyx

From the stem bark of Millettia erythrocalyx, three new compounds, namely, millettocalyxins A-C (1-3), and the new natural product pongol methyl ether (4) were isolated, along with 10 other known compounds. The structures of the new isolates were elucidated on the basis of spectroscopic data interpretation.     

Cacalol derivatives from Roldana angulifolia

Four new modified eremophilanes, angulifolide (1) and angulifolins A-C (2-4), and two new triacetylglucosides (7 and 8) were isolated from Roldana angulifolia, together with several known compounds. The structures of the new compounds were elucidated by spectroscopic analysis and chemical reactions. The absolute configuration of compounds 2 and 3 was established by Mosher ester methodology. Cytotoxicity against selected human cancer cell lines was determined for the more abundant isolated metabolites.     

Steroidal saponins from the bark of Dracaena draco and their cytotoxic activities

From the stem bark of Dracaena draco, three new compounds, namely, draconins A-C (1-3), were isolated, along with 17 known compounds. The structures of the new compounds isolated were elucidated on the basis of spectroscopic data interpretation. Several of the isolated compounds showed potent cytotoxic activities measured on the human leukemia cell line HL-60 (IC(50)'s from 2.0 to 9.7 microM at 72 h). The mechanism by which compounds 1 and 2 display their cytostatic properties is through induction of cell death by apoptosis, as evaluated by fluorescence microscopy and DNA fragmentation.     

Antifeedant rings B and D opened limonoids from Khaya senegalensis.

Three new rings B and D opened limonoids, two mexicanolides named khayanone (1) and 2-hydroxyseneganolide (2) and one rearranged phragmalin limonoid of 1-O-acetylkhayanolide A (3), were isolated together with six known B,D-seco compounds from the acetone extract of the stem bark of Khaya senegalensis. Structures of new compounds were elucidated by spectroscopic means, and the absolute stereochemistry of 1 was established by CD study of the dibenzoate derivative. The insect antifeedant and antiviral activities of the new compounds were also determined.     

Cytotoxic triterpenoids from the leaves of Microtropis fokienensis

Five new triterpenoids, microfokienoxanes A-D (1-4) and 3beta,28-dihydroxy-11alpha-methoxyurs-12-ene (5), were isolated and identified from the leaves of Microtropis fokienensis, along with nine known compounds. The structures of the new compounds were elucidated by spectroscopic methods. The compounds obtained in this investigation were evaluated against a small panel of human cancer cell lines for cytotoxicity. Only compounds 3 and 5 exhibited cytotoxicity (IC50 < or = 5 microg/mL) for one or more cell lines.     

Terpenoids and norlignans from Metasequoia glyptostroboides

Four new terpenoids, metaseglyptorin A (1), metasequoic acid C (2), 12α-hydroxy-8,15-isopimaradien-18-oic acid (3), and (-)-acora-2,4(14),8-trien-15-oic acid (4), and three new norlignans, metasequirins D-F (5-7), were isolated from Metasequoia glyptostroboides, together with 15 known compounds. Structures of the new compounds were determined by analysis of their spectroscopic data, and the absolute configuration of 7 was established by the modified Mosher method. All of the compounds were evaluated for cytotoxicity against five human tumor cell lines.     

β-carboline alkaloids from Stellaria dichotoma var. lanceolata and their anti-inflammatory activity

The present investigation on the chemical constituents of the roots of Stellaria dichotoma var. lanceolata has resulted in the isolation of 21 β-carboline alkaloids, including 13 new compounds, dichotomides III-XIV (1-12) and dichotomine E (13), and eight known compounds. The structures of the new compounds were established on the basis of spectroscopic data analysis. Among these isolated alkaloids, five compounds were examined for their anti-inflammatory potential for the inhibition of NO production in LPS-treated RAW 264.7 cells. All compounds tested exhibited significant inhibition of NO production, with IC(50) values in the range of 11.3 to 19.3 μM.     

Secoiridoid glucosides from Strychnos spinosa

Three new secoiridoid glucosides, stryspinoside (1) and strychosides A (2) and B (3), were isolated, together with 23 known compounds, from the dried branches of Strychnos spinosa. The structures of the new compounds were determined by spectroscopic means.     

Sesquiterpenoids from Saussurea laniceps

Two new guaiane-type sesquiterpenoids (1 and 2) and one new eudesmane-type sesquiterpenoid (3) were isolated from Saussurea laniceps. The structures of these compounds were established by spectroscopic methods, and the absolute stereochemistry of compounds 1 and 2 was determined by Mosher's method. The immunomodulatory activities of compounds 1-3 were evaluated. Of these, compound 3 showed significant inhibition of the proliferation of murine T and B cells in vitro.     

Cypellocarpins A-C, phenol glycosides esterified with oleuropeic acid, from Eucalyptus cypellocarpa

Three new phenol glycosides acylated with (+)-oleuropeic acid, cypellocarpins A (1), B (2), and C (3), along with seven known compounds, were isolated from the dried leaves of Eucalyptus cypellocarpa. Structures of the new compounds were determined on the basis of spectroscopic methods, including 2D NMR experiments and chemical degradation. These new compounds and a known related glucoside (7) showed potent in vitro antitumor-promoting activity in a short-term bioassay evaluating the inhibitory effect on Epstein-Barr virus early antigen activation induced by 12-O-tetradecanoyl phorbol 13-acetate (TPA). These compounds also suppressed an in vivo two-stage carcinogenesis induced with nitric oxide and TPA on mouse skin.     

灯盏花中两个新苷类化合物的结构鉴定

目的 :研究灯盏花的化学成分。方法 :硅胶色谱分离纯化 ,IR ,MS ,NMR及 2D-NMR鉴定结构。结果 :从全草的乙醇提取物正丁醇萃取部位分离并鉴定了2个苷类化合物 ,为 5 ,4′-二羟基黄酮-7-O-β-D-吡喃葡萄糖醛酸丁酯和 3 ,5-二甲氧基苯甲酸-4-O-β-D-吡喃葡萄糖苷。 结论 :2个化合物均为新的苷类化合物。     

New bioactive peroxides from marine sponges of the family plakiniidae

In our continuing program to identify compounds with antifungal properties, the ethanol extracts of two sponges of the family Plakinidae were found to inhibit the growth of the fungal pathogens Candida albicans and Aspergillus fumigatus. From these organisms three new compounds and five known compounds have been identified. A new 1,2-dioxane ring peroxide acid, 1, has been isolated from the sponge Plakortis halichondrioides along with five known compounds. Two new 1,2-dioxolane peroxide acids, 3 and 4, have been isolated from the sponge Plakinastrella onkodes. The structures were established by interpretation of spectral data. The three new compounds exhibit moderate activity against the fungal pathogen C. albicans with MICs of 5, 1.6, and 1.6 microg/mL respectively, for 1, 3, and 4. Compound 1 also showed in vitro inhibition of the fungal pathogen A. fumigatus with an IC(90) value of 5.6 microg/mL.     

Cytotoxic isomalabaricane triterpenes from the marine sponge Rhabdastrella globostellata

Fourteen isomalabaricane triterpenes were isolated from the marine sponge Rhabdastrella globostellata. In addition to the known compounds globostellatic acids A (1) and D (4) and stelliferin riboside (13), 11 of the compounds were new natural products, which included globostelletin (3), eight new globostellatic acid congeners, F to M (2, 5-11), and two new stelliferin ribosides (12 and 14). The isolated compounds were tested against three different cancer cell lines, L5178Y (mouse lymphoma), HeLa (human cervix carcinoma), and PC-12 (rat pheochromocytoma). The isomalabaricane derivatives were found to be selectively active toward the mouse lymphoma cell line L5178Y. The structures were determined by 1D and 2D NMR data and by comparison with spectroscopic data of known related compounds.