Effect of ageing on sterol metabolism in potato tuber slices

When fresh potato tuber slices were incubated with [1-¹⁴C]-sodium acetate, cycloartenol was heavily labelled but no radioactivity was recovered in 24-methylene cycloartanol and free sterols. If potato slices were aged for 0–24 hr before feeding with radioactive acetate, a rapid increase of the label in the sterol precursors and the free sterols was observed. The free sterol content was 5 × higher after ageing for 24 hr. Isofucosterol synthesis was especially stimulated. The synthesis of sterols during the ageing process seems to be related to the appearance of a cycloartenol C24-methylase and may be linked to a biogenesis of membranes.Nomenclature: (1) 4,4,14α-trimethyl 9β, 19β-cyclo-5α-cholest-24-en 3β-ol; (2) 4,4,14α-trimethyl 9β, 19β-cyclo-5α-ergost-24(28)-en 3β-ol; (3) 4α,14α-dimethyl 9β,19β-cyclo 5α-ergost 24(28)-en 3β-ol; (4) 4α, 14α-dimethyl 5α-ergosta 8.24(28)-dien 3β-ol; (5) 4α-methyl 5α-ergosta 7,24(28)-dien 3β-ol; (6) ergosta 5,24(28)-dien 3β-ol; (7) stigmasta 5,Z-24(28)-dien 3β-ol; (8) (24R)-24 methyl cholest 5-en 3β-ol; (9) (24R)-24 ethyl cholest 5-en 3β-ol; (10) (24S)-24 ethyl cholesta 5,E-22(23)-dien 3β-ol; (11) cholest 5-en 3β-ol.     

Enantiospecific synthesis of carbocyclic (+)-(E)-5-(2-bromovinyl)-2'-deoxyuridine

(+)-1-[(1R, 3S, 4R)-3-hydroxy-4-hydroxymethylcyclopentyl]-5-[(E)-2- bromovinyl]-1H,3H-pyrimidin-2,4-dione 10 was synthesized starting from (+)-endo-5-norbornen-2-yl acetate. This chiral educt was obtained by enzymatic hydrolysis of racemic esters of endo-5-norbornen-2-ol.     

Lipase-Catalyzed Kinetic Resolution of (±)-cis-Flavan-4-ol and Its Acetate: Synthesis of Chiral 3-Hydroxyflavanones

Lipase-catalyzed kinetic resolution of (±)-cis-flavan-4-ol and its acetate led to enantiomerically enriched flavan-4-ol and its acetate. These chiral compounds were converted to (2R, 3R)- and (2S, 3S)-3-hydroxyflavanones.     

Synthesis and enantioselective rearrangement of (Z)-4-triphenylmethoxy-2,3-epoxybutan-1-ol enantiomers

Efficient enzyme catalyzed kinetic resolutions of a synthetically useful chiral building block, (Z)-4-triphenylmethoxy-2,3-epoxybutan-1-ol, are reported. The highest selectivities were achieved by Lipozyme TL IM and Amano Lipase PS enzymes in the presence of vinyl acetate. Enantiomeric enrichment of the optically active acetate isomer was accomplished by selective crystallization of the racemic part of the enantiomeric mixture. Enzyme catalyzed hydrolysis of the acetate also provided an optically pure epoxybutanol derivative. O-Benzylation of (+)-(Z)-1-hydroxy-4-triphenylmethoxy-2,3-epoxybutane followed by super base promoted diastereo- and enantio-selective rearrangement resulted in (+)-(2R,3R,1'R)-3-[1-hydroxy-2-(triphenylmethoxy)ethyl]-2-phenyloxetane in >98% ee and de. Configurations of the new optically active products were determined by chemical correlation.     

Studies of the synthesis of biomarkers. VII. Synthesis of 5 alpha-(17R,20R)-14,15-secocholestane

5 alpha-(17R,20R)-14,15-Secocholestane (12) was synthesized from cholesterol (1) in 12 steps. The key intermediate, 5 alpha-cholest-14-en-3 beta-yl acetate (4), underwent ozonization, reduction, hydrolysis, and oxidation to provide 5 alpha-14,15-secocholesta-3,14,15-trione (8). One of the Clemmensen reduction products of 8 is 5 alpha(17R,20R)-14,15-secocholest-15-ol (11); treatment of the alcohol (11) with tosyl chloride and subsequent reduction with lithium aluminum hydride yielded the target molecule (12).     

Synthesis of an aza analogue of 2-deoxy-D-ribofuranose and its homologues.

Azasugars were obtained in one-pot reactions by catalytic reduction reactions of amino group precursors in aldosugars followed by intramolecular reductive amino alkylation reactions. (3R,4S)-4-[(1S)-1,2-Dihydroxyethyl]pyrrolidin-3-ol was obtained from D-xylose by two different strategies through 3-C-cyano-3-deoxy-D-ribo-pentofuranose or 3-C-azidomethyl-3-deoxy-D-ribo-pentofuranose in 6 and 16% overall yields, respectively. The oxidative cleavage of the diol group in the corresponding Fmoc-azasugar followed by deprotection afforded (3R,4R)-4-(hydroxymethyl)pyrrolidin-3-ol. (3R,4S)-4-[(1S,2R)-1,2,3-Trihydroxypropyl]pyrrolidin-3-ol was synthesized from diacetone-D-glucose through 3-deoxy-3-C-nitromethyl-D-allose and the overall yield was 7%.     

A Model to Evaluate the Cytotoxicity of the Fungal Volatile Organic Compound 1-octen-3-ol in Human Embryonic Stem Cells

Microbial growth in damp indoor environments has been correlated with risks to human health. This study was aimed to determine the cytotoxicity of 1-octen-3-ol (“mushroom alcohol”), a major fungal volatile organic compound (VOC) associated with mushroom and mold odors. Using an airborne exposure technique, human embryonic stem cells were exposed for 1 h to different concentrations (0–1,000 ppm) of racemic 1-octen-3-ol and its enantiomers, (R)-(−)-1-octen-3-ol and (S)-(+)-1-octen-3-ol. Cytotoxicity was assayed using both the MTS (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium) assay and the fluorescently tagged Calcein AM-mediated “live and dead” assay. Racemic 1-octen-3-ol and (S)-(+)-1-octen-3-ol exhibited greater cytotoxicity to the undifferentiated human cell line H1 than did (R)-(−)-1-octen-3-ol. The inhibition concentration 50 (IC₅₀) values assessed by the MTS assay for racemic 1-octen-3-ol, (S)-(+)-1-octen-3-ol and (R)-(−)-1-octen-3-ol were, respectively, 109, 98, and 258 ppm. These IC₅₀ values were 40–80-fold lower than that of vapor phase toluene, an industrial chemical used as a positive control in this study. Our report pioneers the modeling of human embryonic stem cells as an in vitro approach to screen the potential toxicity of fungal VOCs. Human embryonic stem cells exposed to 1-octen-3-ol, and its enantiomers in the vapor phase showed more cytotoxicity than those exposed to toluene.     

1,4-benzoquinone attracts males of Rhizotrogus vernus Germ

Two candidate attractants, phenol and 1,4-benzoquinone, a synthetic mixture of typical compounds from green-leaf odours [(Z)-3-hexenyl acetate: (Z)-3-hexen-1-ol: benzaldehyde: (E)-2-hexen-1-ol: 1-hexanol; 100:20:10:1:1] and freshly damaged oak leaves were screened for field attractancy in funnel traps in Hungary. Males of two Rhizotrogus spp. (Coleoptera, Scarabaeidae, Melolonthinae), R. aestivus 01. and R. vernus Germ. were caught in larger numbers. While R. aestivus catches were probably chance captures, male R. vernus was significantly attracted to the baits containing 1,4-benzoquinone. This compound represents a promising basis for the development of a monitoring trap for R. vernus.     

乳孔硫磺菌的化学成分和抗氧化活性

对乳孔硫磺菌子实体不同极性提取物进行了DPPH和ABTS自由基清除能力的测定,并对氯仿和乙酸乙酯提取物进行了分离纯化。结果表明,乳孔硫磺菌的石油醚、氯仿、乙酸乙酯和甲醇提取物均有一定的抗氧化活性,各提取物对两种自由基的清除能力均表现为甲醇提取物＞乙酸乙酯提取物＞氯仿提取物＞石油醚提取物,甲醇提取物对DPPH自由基的清除率最高可达到93.78%;对ABTS自由基的清除率最高可达到62.06%;从氯仿和乙酸乙酯提取物中分离得到10个化合物,分别是：(22E,24R)-5α,8α-过氧麦角甾-6,22-二烯-3β-醇（1）,阿里红酸 A（2）,麦角甾-7,22-二烯-3β-醇（3）,啤酒甾醇（4）,硫色多孔菌酸（5）,(4E,8E)-N-d-2′-hydroxypalmitoyl-1-O-β-d-glycopyranosyl- 9-methyl-4,8-sphingadienine（6）,麦角甾醇（7）,N-(2′-羟基二十四碳酰基)-1,3,4-三羟基-2-氨基-十八烷（8）,烟酸（9）和齿孔酸（10）。其中,化合物2、6、8和9为首次从硫磺菌属真菌中分离得到。     

Dinoflagellate sterols IV: Isolation and structure of 4α,23ξ,24ξ-trimethylcholestanol from the dinoflagellate Glenodiniumhallii

The dinoflagellate $\text{Glenodinium}$$\text{hallii}$ was investigated for its sterol composition. Five of the six sterols were isolated and identified as cholest-5-en-3β-ol, (24ξ)-24-methylcholest-5-en-3β-ol, stigmasta-5,22-dien-3β-ol, (22E,24R)-4α,23,24-trimethyl-5α-cholest-22-en-3β-ol, and 4α,23ξ,24ξ-trimethyl-5α-cholestan-3β-ol.     

陆地革菌的化学成分研究

从陆地革菌(Thelephora terrestris)子实体中分离得到9个已知化合物,经波谱学分析鉴定为:(22E,24R)-麦角甾-7,22-二烯-3β -醇 (1),(22E, 24R)-麦角甾-7, 22-二烯-3β ,5α,6β -三醇 (2),(22E,24R)-麦角甾-4,6,8(14),22-四烯-3-酮 (3),24-亚甲基羊毛甾-8-烯-3β -醇 (4),熊果酸 (5),木栓酮 (6),cerebroside B (7),(2S,3S,4R,2'R)-2-(2'-羟基二十二碳酰氨基)-十八碳烷-1,3,4-三醇 (8),(2S,3S,4R,2'R)-2-(2'-羟基二十三碳酰氨基)-十八碳烷-1,3,4-三醇 (9)。     

Enhanced attraction of Plutella xylostella (Lepidoptera: Plutellidae) to pheromone-baited traps with the addition of green leaf volatiles

Diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), is one of the most serious pests of Brassicaceae crops worldwide. Electrophysiological and behavioral responses of P. xylostella to green leaf volatiles (GLVs) alone or together with its female sex pheromone were investigated in laboratory and field. GLVs 1-hexanol and (Z)-3-hexen-1-ol elicited strong electroantennographic responses from unmated male and female P. xylostella, whereas (Z)-3-hexenyl acetate only produced a relatively weak response. The behavioral responses of unmated moths to GLVs were further tested in Y-tube olfactometer experiments. (E)-2-Hexenal, (Z)-3-hexen-1-ol, and (Z)-3-hexenyl acetate induced attraction of males, reaching up to 50%, significantly higher than the response to the unbaited control arm. In field experiments conducted in 2008 and 2009, significantly more moths were captured in traps baited with synthetic sex pheromone with either (Z)-3-hexenyl acetate alone or a blend of (Z)-3-hexenyl acetate, (Z)-3-hexen-1-ol, and (E)-2-hexenal compared with sex pheromone alone and other blend mixtures. These results demonstrated that GLVs could be used to enhance the attraction of P. xylostella males to sex pheromone-baited traps.     

Synthesis of (3E, 5Z)-3,5-dodecadienylacetate, the sex pheromone of Phtheochroa cranaodes (Lepidoptera: Tortricidae

(3E, 5Z)-3,5-Dodecadienyl acetate, the female sex pheromone of Phtheochroa cranaodes, was regio and stereo-selectively synthesized from 1-octyne and (E)-4bromo-3-buten-1-ol by using Pd(PPh3)4, CuI and piperidine to afford the enyne (5). Further elaboration afforded the target pheromone. The synthetic pheromone was identified with the natural product by its MS and IR, data GLC retention time and biological activity.     

沙棘木蠹蛾(鳞翅目：木蠹蛾科)性信息素组分鉴定及其生物活性

报道了沙棘木蠹蛾性信息素的结构及组分,并报道了不同组分：顺-3-十四碳烯醇;反-3-十四碳烯醇;顺-3-十四碳乙酸酯;反-3-十四碳乙酸酯;顺-7-十四碳烯醇;顺-7-十四碳乙酸酯;顺-9-十四碳乙酸酯的室内触角电位反应和林间诱捕试验。林间诱蛾结果表明2组分和5组分的诱蛾活性高于其它组合。     

攀援孔药花化学成分研究

从攀援孔药花全草95%乙醇提取物中首次分离得到19个化合物,通过波谱数据或与已知物对照,它们分别鉴定为:(2S,3S,4R)-2-[(2R)-2-羟基-二十一酰胺基]-二十一烷-1,3,4-三醇(1)、(2S,3S,4R)-2-二十四酰胺基-十八烷-1,3,4-三醇(2)、胡萝卜甙(3)、β-谷甾醇(4)、(20S,22E,24R)-5α,8α-表二氧-麦角甾-6,22-二烯-3β-醇(5)、6β-羟基-豆甾-4-烯-3-酮(6)、十六烷酸-1-甘油酯(7)、桦木酸(8)、大黄素(9)、二十二烷酸-1-甘油酯(10)、对羟基苯甲醛(11)、十七烷酸-1-甘油酯(12)、金色酰胺醇乙酸酯(13)、十九烷酸-1-甘油酯(14)、棕榈酸(15)(、E)-p-香豆酸(16)、(22E,24S)-24-甲基-5α-胆甾-7,22-二烯-3β,5α,6β-三醇(17)、2-去氧-β-蜕皮激素(18)和auranamide(19)。     

Enantiomeric selectivity in behavioural and electrophysiological responses of Aedes aegypti and Culex quinquefasciatus mosquitoes

1-Octen-3-ol is a kairomone for many haematophagous insects including mosquitoes. Numerous studies have examined the effects of racemic 1-octen-3-ol; however, few studies have investigated the role of individual enantiomers in relation to mosquito attraction. In the present study, we investigated the behavioural and electrophysiological responses of two mosquito species, Aedes aegypti and Culex quinquefasciatus, to individual enantiomers and mixtures of 1-octen-3-ol, employing a laboratory Y-tube olfactometer and single sensillum recordings. The olfactory receptor neurons of both Ae. aegypti and Cx. quinquefasciatus had a significantly higher response to the (R)-1-octen-3-ol enantiomer compared to the (S)-1-octen-3-ol enantiomer at 10-9 g μl-1 to 10-6 g μl-1. Behaviourally, Ae. aegypti was more responsive to the (R)-1-octen-3-ol enantiomer, showing an increase in flight activity and relative attraction compared to Cx. quinquefasciatus. The (R)-1-octen-3-ol enantiomer caused an increase in activation for Cx. quinquefasciatus. However, the most notable effect was from an (R:S)-1-octen-3-ol mixture (84:16) that caused significantly more mosquitoes to sustain their flight and reach the capture chambers (demonstrated by a reduced non-sustained flight activity), suggesting that it may have a behaviourally excitatory effect. For Cx. quinquefasciatus, a reduced relative attraction response was also observed for all treatments containing the (R)-1-octen-3-ol enantiomer, either on its own or as part of a mixture, but not with the (S)-1-octen-3-ol enantiomer. This is the first time enantiomeric selectivity has been shown for Ae. aegypti using electrophysiology in vivo. The implications of these results for exploitation in mosquito traps are discussed.     

三种毒菌的化学成分研究

本文对三种毒菌的化学成分进行了研究。从光盖伞(Psilocybe spp)分离鉴定了4个化合物,经波谱分析鉴定为:(22E,24R)-麦角甾-7,22-二烯-3β-十八烷酸酯(1)、β-胡萝卜苷(2)、(22E,24R)-5α,6α-环氧麦角甾-8,22-二烯-3β,7α-二醇(3)、色氨酸(4);从假褐云斑鹅膏(Amanita pseudoporphyria)分离鉴定了4个化合物:(22E,24R)-3β-羟基-5α,8α-过氧化麦角甾-6,22-二烯(5)、(22E,24R)-麦角甾-7,22-二烯-3β,5α,6β-三醇(6)、1-O-β-D-吡喃葡萄糖基-(2S,3R,4E,8E,2′R)-2-N-(2′-羟基棕榈酰)-9-甲基-4,8-脱氢鞘氨醇(7)、1-O-β-D-吡喃葡萄糖基-(2S,3R,4E,8E,2′R)-2-N-(2′-羟基十八烷酰)-9-甲基-4,8-脱氢鞘氨醇(8);大青褶伞(Chlorophyllum molybdites)发酵菌丝体分离鉴定了4个化合物:5、6、(22E,24R)-5α,6α-环氧麦角甾-8(14),22-二烯-3β,7α-二醇(9)、(22E,24R)-麦角甾-7,22-二烯-3β-醇(10)。除化合物9外其它化合物均为首次从以上相应毒菌中分离得到。     

Epimerisation of 3β-ol to 3α-ol steroid alkaloids by Nocardia restrictus

(22S,25S)-5α-tomatanin-3β-ol, N-acetyl-(22S,25S)-5α-tomatanin-3β-ol, (22R,25R)-5α-tomatanin-3β-ol and (22R,25S)-22,26-epimino-5α-cholestane-3β,16β-diol are transformed by Nocardia restrictus into corresponding 3α-ol compounds with yields from 70 to 5%.     

Oxygenated lycopene and dehydrated lutein in tomato puree

Oxygenated lycopenes, (2S*,5S*,6R*)-2,6-cyclolycopene-1-methoxy-5-ol, (2S*,5S*,6R*)-1,16-didehydro-2,6-cyclolycopene-5-ol and (3R,6'R)-3-hydroxy-3',4'-didehydro-beta,gamma-carotene (anhydrolutein I) were isolated from tomato puree. The structures of these compounds were elucidated on the basis of spectroscopic evidence.     

蓝柄丽齿菌的化学成分

从担子菌亚门蓝柄丽齿菌(Calodon suaveolens)中首次分离得到8个化合物,通过波谱学技术并借助必要的化学方法最终确定结构,它们是：(22E,24R)-麦角甾-7,22-二烯-3β-醇(1),(22E,24R)-5α,8α-过氧麦角甾-6,22-二烯．3β-醇(2),(22E,24R)-麦角甾．5,7,22-三烯-3β-醇(3),(22E,24R)-3β-羟基麦角甾-5,22-二烯-7-酮(4),对羟基苯甲酸(5),尿嘧啶(6),polyozellin(7),(4E,BE）-2-N-(2’-羟基棕榈酰)-1-O-β-D-吡喃葡萄糖基-9-甲基-4,8-sphingadienine(8)。