Two new spongian diterpenes from Coscinoderma mathewsi

Two new spongian diterpenes were isolated from the sponge, Coscinoderma mathewsi. One possesses a tricyclic skeleton bearing an aldehyde function, the other is a tetracyclic lactol. The structures of two compounds are elucidated by spectral method.     

Novel cassane and cleistanthane diterpenes from Myrospermum frutescens: absolute stereochemistry of the cassane diterpene series

Four new diterpenes (1-4) were isolated from the leaves of Myrospermum frutescens as minor constituents. Chagresnol (1), 6beta,18-diacetoxycassan-13,15-diene (2), and chagreslactone (3) possess cassane skeletons, while chagresnone (4) exhibits a cleistanthane skeleton. Molecular structures and their relative stereochemistries were elucidated using NMR spectroscopy in combination with UV, IR, and MS spectral data. Although compound 2 was previously reported as a synthetic product, we report its first isolation as a natural product. Derivative products (10-13) were obtained to test their activities against Chagas's disease. In addition, the absolute stereochemistry of the previously isolated cassane diterpene 5 from M. frutescens is presented.     

迷迭香中2个新松香烷型二萜化合物

目的研究迷迭香Rosmarinus officinalis的化学成分及其活性。方法采用多种柱色谱对迷迭香地上部分甲醇提取物进行分离纯化;通过波谱数据对化合物进行结构鉴定;采用磺酰罗丹明B比色法(SRB法)对所得化合物进行细胞毒活性测试。结果从迷迭香的甲醇提取物中分离得到2个新的松香烷型二萜类化合物和8个已知二萜类化合物,分别鉴定为7-异丙氧基-表异迷迭香酚(1)、7-异丙氧基-迷迭香醌(2)、迷迭香酚(3)、7-甲氧基-迷迭香酚(4)、表迷迭香酚(5)、7-甲氧基-表异迷迭香酚(6)、rosmaquinoneB(7)、鼠尾草酚(8)、galdosol(9)和pisiferal(10)。结论化合物1和2为新化合物,分别命名为7-异丙氧基-表异迷迭香酚和7-异丙氧基-迷迭香醌。活性测试结果表明所有二萜类化合物均无明显细胞毒活性。     

中华青牛胆中2个新的木脂素葡萄糖苷

目的研究中华青牛胆Tinospora sinensis的化学成分及其体外抗神经炎症活性。方法采用硅胶、Sephadex LH-20、ODS和制备型HPLC等色谱分离技术对化学成分进行分离纯化,并运用理化性质结合现代谱学(ESI-MS、1H-NMR、13C-NMR、ECD)解析技术进行结构鉴定。利用脂多糖(LPS)诱导的BV-2小胶质细胞模型进行抗神经炎症活性筛选。结果从中华青牛胆藤茎的95%乙醇水提取物中分离得到13个化合物,分别鉴定为中华青牛胆木脂苷C(1)、中华青牛胆木脂苷D(2)、裂环异落叶松脂醇-9-O-β-吡喃葡萄糖苷(3)、(+)-松脂醇-4-O-β-D-吡喃葡萄糖苷(4)、(+)-丁香脂素(5)、tanegoside A(6)、(E)-3-[(2,3-trans)-2-(4-hydroxy-3-methoxyphenyl)-3-hydroxymethyl-2,3-dihydrobenzo[b][1,4]dioxin-6-yl]-N-(4-hydroxy-phenethyl)acrylamide(7)、银钩花胺酰B(8)、反式-N-p-香豆酰基酪胺(9)、N-反式-阿魏酰酪胺(10)、N-反式-咖啡酰酪胺(11)、克罗酰胺K(12)、顺式-克罗酰胺K(13)。发现7个化合物具有抗神经炎症活性。结论所分离鉴定的化合物包括木脂素和生物碱,其中化合物1和2为新化合物,3、5、7、8、10~13为首次从该植物中分离得到。化合物9和10的活性强于阳性对照米诺环素。     

假升麻中2个新的单萜苷类化合物

目的研究假升麻Aruncus sylvester根的化学成分。方法采用大孔树脂、硅胶及反相ODS柱色谱等方法进行分离和纯化,并综合运用NMR、HR-ESI-MS等波谱手段以及ECD计算等方法鉴定化合物的结构。结果从假升麻乙醇提取物正丁醇萃取部分中分离得到2个新的单萜苷,分别鉴定为(2E,4S,5R)-4-hydroxy-3-[2-(β-D-glucopyranosyloxy)ethylidene]-5-(2-methylprop-1-en-1-yl)dihydrofuran-2(3H)-one(1)、(2Z,4S,5R)-4-hydroxy-3-[2-(β-D-glucopyranosyloxy)ethylidene]-5-(2-methylprop-1-en-1-yl)dihydrofuran-2(3H)-one(2)。结论化合物1和2均为新化合物,分别命名为假升麻苷A和假升麻苷B。     

Sulfur-containing bis-iridoid glucosides and iridoid glucosides from Saprosmas cortechinii

Six new sulfur-containing bis-iridoid glucosides, saprosmosides A-F (1-6), were isolated from the leaves of Saprosma scortechinii. From the stems of this same plant, two new iridoid glucosides, 3,4-dihydro-3-methoxypaederoside (8) and 10-O-benzoyldeacetylasperulosidic acid (12), were isolated. Their structures were elucidated by means of chemical, NMR, and mass spectroscopic methods. Additionally, 11 known iridoid glucosides were isolated and characterized as deacetylasperuloside, asperuloside, paederoside (7), deacetylasperulosidic acid (9), scandoside, asperulosidic acid, 10-acetylscandoside, paederosidic acid (10), 6-epi-paederosidic acid (11), methylpaederosidate, and monotropein. The structures of the new bis-iridoid glucosides were formed by intermolecular esterification between the glucose and carboxyl groups of three monomeric iridoid glucosides (7, 9, and 10).     

Two new stilbene dimer glucosides from grape (Vitis vinifera) cell cultures

Two new stilbene dimer glucosides, resveratrol (E)-dehydrodimer 11-O-beta-D-glucopyranoside (1) and resveratrol (E)-dehydrodimer 11'-O-beta-D-glucopyranoside (2), were isolated together with the known resveratrol (E)-dehydrodimer (3) and pallidol (4) from Vitis vinifera cell cultures. The structures and stereochemistry of the new compounds were determined on the basis of spectroscopic data analysis. Compounds 1 and 2 are dimers that belong to a new type of oligostilbene formed from a resveratrol unit and a resveratrol glucoside unit. Compounds 1 and 3 exhibited nonspecific inhibitory activity against cyclooxygenase-1 and -2, with IC(50) values in the range of 5 microM, whereas compound 4 was approximately 10-fold less active.     

Two new ring A-rearranged clerodane diterpenes, dunniana acids A and B, from Clausena dunniana

Two ring A-rearranged clerodane diterpenes named dunniana acids A (1) and B (2) were isolated from the aerial parts of Clausena dunniana. The structures of 1 and 2 were determined using spectral methods.     

Neo-clerodane diterpenes from Salvia herbacea

Chemical investigation of the aerial parts of Salvia herbacea led to the isolation of eight new neo-clerodane diterpenes (1-8), named tehuanins A-H, and three known compounds. The structures of these compounds were determined by analysis of their spectroscopic data. Three of the new diterpenes possess a 1,8-epoxy group (1-3). This unusual structural feature was confirmed by X-ray diffraction of 1. The structure of the previously isolated 1α,10α-epoxysalviarin was revised. The absolute configuration of 6 was established by X-ray diffraction analysis of its bromo derivative 6a. Cytotoxic and anti-inflammatory activities of these diterpenes were examined. None of the compounds were considered to be cytotoxic; however, compound 7 exhibited anti-inflammatory activity comparable to that of indomethacin.     

Furanolabdane diterpenes from Hypoestes purpurea

Four new furanolabdane diterpenes, hypopurin A (1), hypopurin B (2), hypopurin C (3), and hypopurin D (4), together with eight lignans, alpha-O-methylcubebin, beta-O-methylcubebin, hinoquinin, helioxanthin, 7-hydroxyhinokinin, dehydroxycubebin, justicidine E, and (-)-hibalactone, as well as two triterpenes, lupeol and betulin, were isolated from the dried aerial part of Hypoestes purpurea. The structures of 1-4 were elucidated mainly on the basis of NMR and MS. Compound 1 was found to be moderately cytotoxic toward the KB cell line with an IC(50) value of 9.4 microM.     

Labdane diterpenes from Stachys plumosa

Three new labdane diterpenoids were isolated from the aerial parts of Stachys plumosa. The first two (1, 2) were the dextrorotatory enantiomers of the known 6-deoxyandalusol and 13-epijabugodiol. Structures were determined using NMR and MS techniques. The absolute stereochemistry of the third compound (3) was not experimentally proved.     

Cytotoxic diterpenes from Scoparia dulcis

Four new labdane-derived diterpenes, iso-dulcinol (1), 4-epi-scopadulcic acid B (2), dulcidiol (4), and scopanolal (5), together with two known diterpenes, dulcinol/scopadulciol (3) and scopadiol (6), were isolated from the aerial parts of Scoparia dulcis. The structures were determined by extensive NMR studies. The crude extracts as well as the pure diterpenes showed cytotoxicity against a panel of six human stomach cancer cell lines.     

Bioactive diterpenes from Callicarpa longissima

Investigation of the leaves and twigs of Callicarpa longissima resulted in the isolation of four new compounds (1-4), callilongisins A-D, and five known compounds, ursolic acid, 3-oxoanticopalic acid, (E)-6β-hydroxylabda-8(17),13-dien-15-oic acid, 5-hydroxy-3,6,7,4'-tetramethoxyflavone, and artemetin. Compounds 1-3 are 3,4-seco-abietane-type diterpenoids, and compound 4 is an analogue of a labdenoic-type diterpene. The structure of compound 1 was confirmed by X-ray crystallographic analysis. Cytotoxicity against a human prostate cancer cell line (PC3) and anti-inflammatory activities of the isolated compounds were evaluated.     

Antimicrobial diterpenes from Trigonostemon chinensis

Five new diterpenes, trigonochinenes A-E (1-5), and two known ones, 3,4- seco-sonderianol (6) and 3,4- seco-sonderianic acid (7), were isolated from the aerial part of Trigonostemon chinensis. Compounds 1-4 possess a rare 3,4-seco-cleistanthanic skeleton, and compound 5 is a highly aromatized tetranorditerpene. Structures of these compounds were elucidated by spectroscopic analysis. The antimicrobial activities of compounds 1-7 were evaluated against a panel of bacteria and fungi.     

ent-kauranoid diterpenes from Artemisia sacrorum

A new ent-kauranoid diterpene diglycoside has been isolated from Artemisia sacrorum along with two known ent-kauranoid diterpenes. Their structures are elucidated by means of nmr analysis (DEPT, 1H-1H COSY, 1H-13C COSY, and 1H-1H decoupling).     

New diterpenes from Croton insularis

Two new diterpenes (1 and 2) have been isolated from the aerial parts of Croton insularis. Their structures have been established by NMR and mass spectral data, and the absolute configuration of 1 and related trachylobane diterpenes was determined through a series of chemical correlations.     

Clerodane diterpenes from Tinospora rumphii

Two new diterpenes (1 and 2) were obtained from the leaves of Tinospora rumphii, along with the known compounds tinotufolin D and vitexilactone. The structures of compounds 1 and 2 were established on the basis of spectroscopic studies.     

Antibacterial diterpenes from Calceolaria pinifolia

Two new isopimaranes, 19-methylmalonyloxy-ent-isopimara-8(9),15-diene (5) and 19-malonyloxy-ent-isopimara-8(9),15-diene (6), were isolated using bioassay-guided fractionation of the CH(2)Cl(2)-MeOH (1:1) extract of the aerial part of Calceolaria pinifolia along with eight other diterpenes (1-4, 7-10) and two triterpenes (11, 12). All compounds were assayed against Staphylococcus aureus (SA), methicillin-resistant S. aureus (MRSA), Bacillus subtilis (BS), and Escherichia coli (EC). 4-Epi-dehydroabietinol (2) and ent-isopimara-9(11),15-diene-19-ol (8) were found to be active against MRSA with MIC values of 8 and 2 microgram/mL, respectively. Mechanistic studies of 8 in BS suggested rapid and nonspecific inhibition of uptake and incorporation of radiolabeled precursors into DNA, RNA, and protein consistent with membrane-damaging effects in bacteria. Compound 8 did not afford protection against an acute infection with SA in mice.     

Oligo- and macrocyclic diterpenes in thymelaeaceae and euphorbiaceae occurring and utilized in Yunnan (Southwest China) 1. Daphnane type diterpene esters from Daphne feddei

From roots of the Chinese folk medical plant Daphne feddei Lévl. three Daphne factors F₁, F₂ and F₃ have been isolated. They proved identical with the known daphnane type 9,13,14-orthoesters huratoxin (F₁), genkwadaphnin (F₂) and with the known daphnane type 14-ester prohuratoxin (F₃). From stem bark of the plant a new factor F₄ was obtained and identified as the 1,2-dihydro derivative of the known daphnane type 9,13,14-orthoester daphnetoxin. The factors F₁–F₄ exhibit moderate to strong irritant activity on the mouse ear. F₄ assayed in the standard protocol 16 for tumor promoting activity on the back skin of mice was nearly inactive. Certain structure/activity relationships are pointed out along the conceptual idea to develop diterpene structures with diminished or abolished irritant and tumor promoting activities but retained immune stimulating, differentiating or otherwise antineoplastic activities.     

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.