(R)-乙基-2-吡啶亚砜与(4R，5R)-TADDOL包结晶体 ［C7H9NOS．C31H30O4］的晶体结构分析

(R)-乙基-2-吡啶亚砜与(4R，5R)-二(羟基-二苯基-甲基)-2，2-二甲基-1，3-二氧戊环(TADDOL)可以形成物质的量比为1∶1的手性包结晶体， X射线衍射分析确定该晶体属单钭晶系， P2     

三个新甾体皂甙元的结构鉴定

从中药蒺藜Tribulus terrestrisL.(Zygophyllaceae）中分离纯化得到5个 甾体皂甙元，经IR，2D-NMR和MS等波谱技术分别鉴定为：海可皂甙元(1)，25(R)-螺 甾烷-4—烯—3，12—酮(2)，25(R)·螺甾烷—3，5-二烯—12—酮(3)，25(R)-螺 甾烷-4—烯—2β，3α-二羟基—12—酮(4)和25(R)—螺甾烷—24β—羟基-4—烯 —3，12—酮(5)，其中化合物3-5为新化合物．     

手性双二茂铁基配体的合成、表征及固体CD光谱

以甲酰基二茂铁(1)和手性1,2-二苯基乙二胺[(1R, 2R)-1,2-二苯基乙二胺(2R), (1S,2S)-1,2-二苯基乙二胺(2S)]为原料, 经缩合、还原和N-烷基化反应, 制备了一对新型手性四齿双二茂铁基配体[N,N’-二(二茂铁基甲基)-N,N’-二(2-羟基丙基)-(1R,2R)-1,2-二苯基乙二胺(5R)和N,N’-二(二茂铁基甲基)-N,N’-二(2-羟基丙基)-(1S,2S)-1,2-二苯基乙二胺(5S)]. 用元素分析、红外(IR)、质子核磁共振(1H NMR)、紫外-可见(UV-Vis)、固体圆二色(CD)光谱等对手性产物(3R-5S)进行了表征. 固体CD光谱研究表明, 配体5R(或5S)的手性特征和4R(或4S)相似而与3R(或3S)却有一定差别.     

α-葡萄糖苷酶抑制剂Radicamine B的合成

以D-阿拉伯糖为原料,依次合成了中间体(2R,3R,4R)-2,3,5-三-O-苄氧基-4-羟基-O-叔丁基二甲基硅基-戊醛肟(3),(2R,3S,4S)-2,3,5-三-O-苄氧基-4-碘-O-叔丁基二甲基硅基-戊醛肟(4)和(2R,3R,4R)-3,4-二-O-苄氧基-2-(苄氧甲基)-3,4-二氢-2H-吡咯-1-醇(5);5与芳基Grignard试剂进行高立体选择性的加成反应制得(2R,3R,4R,5R)-3,4-二-O-苄氧基-2-[4-(苄氧基)苯基)]-5-吡咯-1-醇(6);6经催化氢化合成Radicamine B,总收率18.5%。3和4为新化合物,其结构经1HNMR,MS和元素分析表征。     

二醇及氨基醇类鬼臼毒素衍生物的合成

以天然产物鬼臼毒素(1)为原料，合成了四种二醇及氨基醇类鬼臼毒素衍生物：4-O-乙基表鬼臼苦醇(4)，(1R,2S,3R,4S)-1-3',4',5'-三甲氧基苯基-2-氨甲基-3-羟甲基-4-乙氧基-6,7-亚甲二氧基-1,2,3,4-四氢萘(5)，(1R,2S,3R,4S)-1-3',4',5'-三甲氧基苯基-3-羟甲基-2-氨基-4-乙氧基-6,7-亚甲二氧基-1,2,3,4-四氢萘(6)和4-O-异丙基表鬼臼苦醇(7)。4～7及中间产物8～11都是新化合物。     

Asymmetric Syntheses of Osmundalactones and 5-Hydroxy-2-hexen 4-olides from 4-Benzyloxy-5-hydroxy-2（E）-hexenoate

( )-(4S,5R)-Osmundalactone 1 was isolated from the fungus Paxillus atrotomentosus (Paxillaceae) by Buchanan1. (-)-(4R,5S)-Osmundalactone 1 and ( )-(4R,5S)-5-hydroxy- 2-hexen-4-olide 2 were isolated from Osmunda japonica (Osmundaceae) as feeding inhibitors…     

毛华菊中倍半萜内酯类化学成分研究

采用溶剂提取法, Diaion HP-20、Sephadex LH-20葡聚糖凝胶、硅胶及制备高效液相等色谱方法,对毛华菊的化学成分进行分离纯化,并利用现代波谱技术对已分离得到的化合物进行结构鉴定.从毛华菊的氯仿部位分离得到4个新化合物,其结构类型属于愈创木内酯衍生物,分别命名为(1S,5R,6S,7S,10S)-愈创木-3,11(13)-二烯-2-酮-12,6-内酯(1)、(1S,5R,6R,7R,8S,10S)-8-异丁酰氧基-愈创木-3,11(13)-二烯-2-酮-12,6-内酯(2)、(1S,5R,6R,7R,8S,10S)-8-(2'-甲基)丁酰氧基-愈创木-3,11(13)-二烯-2-酮-12,6-内酯(3)和(1R,5R,6R,7R,8S,10S,11S)-8-乙酰氧基-愈创木-3-烯-2-酮-12,6-内酯(4),以及2个已知化合物matricarin (5)和11,13-dehydromatricarin (6).     

新型含七元醚环的脯氨酸衍生物的合成

以L-谷氨酸和苯甲醛为起始原料,经7步反应合成了重要中间体(2S,5R)-1-苄基-5-(2-羟乙基)吡咯烷-2-羧酸叔丁酯(1),总产率19%;1经TBDMSCl保护羟基后,用10%Pd/C催化氢解去除苄基制得游离胺(2S,5R)-5-(2-二甲基叔丁基硅氧烷基乙基)吡咯烷-2-羧酸叔丁酯(3);3与Boc-β-Cl-ala,在碱性条件下偶合得氯代烃消去产物(2S,5R)-1-[(2-叔丁氧甲酰胺基)丙烯酰基]-5-(2-二甲基叔丁基硅氧烷基乙基)吡咯烷-2-羧酸叔丁酯(4),或在中性条件下偶合得(2S,5R)-1-[(R)-2-叔丁氧甲酰胺基-3-氯丙酰基]-5-(2-二甲基叔丁基硅氧烷基乙基)吡咯烷-2-羧酸叔丁酯(5);4或5经四丁基氟化铵去除TBDMS保护并发生关环反应合成了新型的七元醚环化合物(4R,7S,9R)-4-甲基-4-叔丁氧甲酰胺基-5-羰基-3-氧杂氮杂卓[1,4]并吡咯[1,2-d]-7-羧基叔丁酯(简称6);6于室温在氯仿中静置2 d~3 d自发转换为其构象异构体(4S,7S,9R)-6(简称6’,6/6’=1/9),其结构经1H NMR,13C NMR,2D NMR和HR-ESI-MS表征。     

新型手性N-烷基-3-蒎胺类化合物的合成及其抑菌活性的研究

以(1S,5S)-(－)-α-蒎烯为原料合成了系列新型(1S,2S,3S,5R)-N-烷基-3-蒎胺类化合物. (－)-α-蒎烯经硼氢化氧化、重铬酸吡啶盐(PDC)氧化得到(1S,2S,5R)-(－)-3-蒎酮; 在BF3•(C2H5)2O催化下(1S,2S,5R)-(－)-3-蒎酮与伯胺化合物反应生成Schiff碱, 再经KBH4或NaBH4还原得到(1S,2S,3S,5R)-N-烷基-3-蒎胺类化合物. 采用FT-IR, 1H NMR, 13C NMR和GC-MS等分析手段对合成所得(1S,2S,5R)-N-烷基-3-蒎烷亚胺和(1S,2S,3S,5R)-N-烷基-3-蒎胺类化合物的结构进行了表征. 考察了(1S,2S,3S,5R)-N-烷基-3-蒎胺类化合物对大肠杆菌(E. coli)、金黄色葡萄球菌(S. aureus)、枯草芽胞杆菌(B. subtilis)、荧光假单胞菌(P. fluorescens)、白色念珠菌(C. albicans)、黑曲霉(A. niger)和米根霉(R. oryzae)等细菌和真菌的抑菌和杀菌活性. 结果表明(1S,2S,3S,5R)-N-正庚基-3-蒎胺对真菌和细菌均表现出良好的杀菌和抑菌活性.     

Chiral Synthesis of the Intermediate of (-)-Gibberellin A_(12)

Inthepreviouspapers,wereportedtotalsynthesesofditerpenoidsofC-2oQseriessuchas(+)-podocarpicacid(:),andcalabarbeanalkaloid(-)-physostigmine("from(S)-(-)-2-methyl-2-(2'-nitrovinyl)-5-valerolactone.Herewereportasynthesisofthekeyintermediate(l)for(-)-gibberellinA,=using(R)-(+)-2-methyl-2-(2'-nitrovinyaSachiralbuildingblock.(R)-(+)-2-methyl-2-(2'-nitrovinywassynthesizedaccordingtoliteratUremethod(3)in95%yieldand9l%ee.TheMichaeladditionofbenZylInagnesiumbromideto(R)-nitroolefm2affordedadiastereo…     

Studies on the constituents of Broussonetia species VIII. Four new pyrrolidine alkaloids, broussonetines R, S, T, and V and a new pyrroline alkaloid, broussonetine U, from Broussonetia kazinoki Sieb

Four new pyrrolidine alkaloids, broussonetines R, S, T, and V and a new pyrroline alkaloid, broussonetine U were isolated from the branches of Broussonetia kazinoki SIEB. (Moraceae) in low yield. Broussonetines R, S and T were formulated as (2R,3R,4R,5R)-2-hydroxymethyl-3,4-dihydroxy-5-[(1R)-1-hydroxy-3-[6-(4-hydroxybutyl)-cyclohexy-2-on-1(6)-enyllpropyl] pyrrolidine (1), (2R,3R,4R,5R)-2-hydroxymethyl-3,4-dihydroxy-5-[(1R,10S)-1,10,13-trihydroxytridecyl] pyrrolidine (2), (2R,3R,4R,5R)-2-hydroxymethyl-3,4-dihydroxy-5-[(1R,5S)-1,5, 13-trihydroxy-10-oxo-tridecyl] pyrrolidine (3). And broussonetines U and V were proposed to be (2S,3S,4S)-2-hydroxymethyl-3, 4-dihydroxy-5-(9-oxo-13-hydroxytridecyl)-5-pyrroline (4), (2R,3S,4R,5R)-2-hydroxymethyl-3,4-dihydroxy-5-[(E)-9-oxo-13-hydroxy-3-tridecenyl] pyrrolidine (5), respectively, by spectroscopic and chemical methods.     

Studies on the constituents of Broussonetia species X. Six new alkaloids from Broussonetia kazinoki Sieb.

Six new alkaloids, broussonetines W, X, M1, U1, J3, and J2 (1-6) were isolated from the branches of Broussonetia kazinoki SIEB. (Moraceae) as minor constituents. They were formulated as (2R,3R,4R,5R)-2-hydroxy-methyl-3,4-dihydroxy-5-17-(cyclohexy-2-on-1(6)-enyl)heptyllpyrrolidine (1), (2R,3S,4R,5R)-2-hydroxymethyl-3,4-dihydroxy-5-17-(cyclohexy-2-on-1(6)-enyl)heptyl]pyrrolidine-4-O-beta-D-glucopyranoside (2), (2R,3R,4R,5R)-2-hydroxymethyl-3,4-dihydroxy-5-[(9R)-9,13-dihydroxytridecyl]- pyrrolidine (3), (2S,3S,4S)-2-hydroxymethyl-3,4-dihydroxy-5-(10-oxo-13-hydroxytridecyl)-5- pyrroline (4), (2R)-2-[(IS,2S)-1,2-dihydroxy-8-1(2R,3R,4R,5R)-5-(2-hydroxymethyl-3,4-dihydroxy-1-acetylpyrrolidinyl)loctyl]piperidine (5), (2R)-2-[(1S,2S)-1,2-dihydroxy-8-[(2R,3R, 4R,5R)-5-(2-hydroxymethy]-3,4-dihydroxypyrrolidinyl)]octyl]piperidine (6).     

Chiral Cyclopentane-Based Mimics of D-myo-Inositol 1,4,5-Trisphosphate from D-Glucose

Two routes from D-glucose to chiral, ring-contracted analogs of the second messenger D-myo-inositol 1,4,5-trisphosphate are described. Methyl alpha-D-glucopyranoside was converted by an improved procedure into methyl 4,6-O-(p-methoxybenzylidene)-alpha-D-glucopyranoside (6) and thence into methyl 2-O-benzyl-3,4-bis-O-(p-methoxybenzyl)-alpha-D-gluco-hexodialdopyranoside (1,5) (14) in four steps. In the first ring-contraction method 14 was converted into methyl 2-O-benzyl-6,7-dideoxy-3,4-bis-O-(p-methoxybenzyl)-alpha-D-gluco-hept-6-enopyranoside (1,5) (15), which on sequential treatment with Cp(2)Zr(n-Bu)(2) followed by BF(3).Et(2)O afforded a mixture of (1R,2S,3S,4R,5S)-3-(benzyloxy)-4-hydroxy-1,2-bis[(p-methoxybenzyl)oxy]-5-vinylcyclopentane (16) and its 4S,5R diastereoisomer 17. Removal of the p-methoxybenzyl groups of 16 and subsequent phosphorylation and deprotection afforded the first target compound, (1R,2R,3S,4R,5S)-3-hydroxy-1,2,4-tris(phosphonooxy)-5-vinylcyclopentane (3). In the second route, intermediate 14 was subjected to SmI(2)-mediated ring contraction to give (1R,2S,3S,4R,5S)-3-(benzyloxy)-4-hydroxy-5-(hydroxymethyl)-1,2-bis[(p-methoxybenzyl)oxy]cyclopentane (20). Benzylation of 20 provided (1R,2S,3S,4R,5S)-3-(benzyloxy)-6-[(benzyloxy)methyl]-4-hydroxy-1,2-bis[(p-methoxybenzyl)oxy]cyclopentane (22) and (1R,2S,3S,4R,5S)-3,4-bis(benzyloxy)-5-(hydroxymethyl)-1,2-bis[(p-methoxybenzyl)oxy]cyclopentane (21), which were elaborated to the target trisphosphates (1R,2R,3S,4R,5S)-3-hydroxy-5-(hydroxymethyl)-1,2,4-tris(phosphonooxy)cyclopentane (4) and (1R,2S,3R,4R,5S)-1,2-dihydroxy-3,4-bis(phosphonooxy)-5-[(phosphonooxy)methyl]cyclopentane (5), respectively. Both 3 and 4 mobilized intracellular Ca(2+), but 4 was only a few fold less potent than D-myo-inositol 1,4,5-trisphosphate, demonstrating that effective mimics can be designed that do not bear a six-membered ring.     

Diastereoselective hydroxylation of 6-substituted piperidin-2-ones. An efficient synthesis of (2S,5R)-5-hydroxylysine and related alpha-amino acids

The synthesis of (2S,5R)-5-hydroxy-6-oxo-1,2-piperidinedicarboxylates (5) and related (3S,6R)-3-hydroxy-6-alkyl-2-oxo-1-piperidinecarboxylates has been developed. The approach is based on the asymmetric hydroxylation of enolates generated from the corresponding N-protected-6-substituted piperidin-2-ones. The utility of 5a as a precursor in the synthesis of (2S,5R)-5-hydroxylysine (1), an amino acid unique to collagen and collagen-like proteins, has also been demonstrated. (2S)-6-oxo-1,2-piperidinedicarboxylates (6) required for hydroxylation studies were prepared in 38-74% yield, starting from conveniently protected aspartic acid as inexpensive chiral adduct. Hydroxylation of 6 to 5 proceeds in high yield and excellent diastereoselectivity by treatment of their Li-enolate with (+)-camphorsulfonyloxaziridine at -78 degrees C. Ring opening of di-tert-butyl (2S,5R)-6-oxo-1,2-piperidinedicarboxylate ((5R)-5a) under reductive conditions afforded the corresponding 1,2-diol (17) in 91%, which was further transformed to (2S,5R)-5-hydroxylysine in four steps (84%). 17 is also a versatile intermediate in the preparation of tert-butyl (2S,5R)-2-[(tert-butoxycarbonyl)amino]-5-hydroxy-6-iodohexanoate (3) and tert-butyl (2S)-2-[(tert-butoxycarbonyl)amino]-4-[(2R)-oxiranyl]butanoate (4), two amino acid derivatives used in the total synthesis of the bone collagen cross-link (+)-pyridinoline (2a).     

Design, synthesis, and 1,3-dipolar cycloaddition of (5R)- [and (5S)]-5,6-dihydro-5-phenyl-2H-1,4-oxazin-2-one N-oxides as chiral (E)-geometry-fixed alpha-alkoxycarbonylnitrones

Optically pure (5R)- [and (5S)]-5,6-dihydro-5-phenyl-2H-1, 4-oxazin-2-one N-oxides [(5R)- and (5S)-2] were designed as chiral (E)-geometry-fixed alpha-alkoxycarbonylnitrones 1. The nitrones (5R)- and (5S)-2 were synthesized by three-step oxidation of (R)- and (S)-phenylglycinols [(R)- and (S)-3], condensation of the resulting (R)- and (S)-2-hydroxylamino-2-phenylethanols [(R)- and (S)-5] with glyoxylic acid, and cyclization of the intermediary nitrones (R)- and (S)-6b. The nitrone (5R)-2reacted with olefins 7-14 under mild conditions to afford the corresponding cycloadducts 15-22 as the main products via the least sterically demanding exo modes. Cycloadduct 30 obtained from (5S)-2 and cyclopentadiene was effectively elaborated to (1S,4S, 5R)-4-benzyloxycarbonylamino-2-oxabicyclo[3.3.0]oct-7-en-3-one (28), the key synthetic intermediate of carbocyclic polyoxin C.     

Synthesis and pharmacological activity of 4-amino-5-chloro-2-methoxy-N-[(2S,4S)-1-ethyl-2-hydroxymethyl-4- pyrrolidinyl]benzamide (TKS159) and its optical isomers

Of 4-amino-5-chloro-2-methoxy-N-(1-ethyl-2-hydroxymethyl-4- pyrrolidinyl)benzamide, four optical isomers, (2S,4S)-1 (TKS159), (2S,4R)-25, (2R,4S)-26 and (2R,4R)-27, were prepared from optically active 4-amino-1-ethyl-2-hydroxymethylpyrrolidine di-p-toluenesulfonate [(2S,4S)-14, (2S,4R)-17, (2R,4S)-20 and (2R,4R)-23, respectively]. The requisites, (2S,4S)-14, (2S,4R)-17, (2R,4S)-20 and (2R,4R)-23, were prepared from a commercially available trans-4-hydroxy-L-proline. The absolute configurations of (2S,4S)-1 (TKS159), (2S,4R)-25, (2R,4S)-26 and (2R,4R)-27 were spectroscopically determined. Of the benzamide derivatives, four optical isomers, (2S,4S)-1, (2S,4R)-25, (2R,4S)-26 and (2R,4R)-27, showed a relatively potent affinity for 5-hydroxytryptamine 4 (5-HT4) receptors in a radioligand binding assay ([3H]GR113808). The activities of 25-27 were less effective than that of 1 for the gastric emptying of a phenol red semisolid meal in rats. All this suggests that the most potent of the isomers was 4-amino-5-chloro-2-methoxy-N-[(2S,4S)-1-ethyl-2- hydroxymethyl-4-pyrrolidinyl]benzamide (1).     

Studies on the constituents of Broussonetia species. VII. Four new pyrrolidine alkaloids, broussonetines M, O, P, and Q, as inhibitors of glycosidase, from Broussonetia kazinoki SIEB

Four new pyrrolidine alkaloids, broussonetines M, O, P, and Q, were isolated from the branches of Broussonetia kazinoki SIEB, (Moraceae). Broussonetines M, O, P, and Q were formulated as (2R,3R,4R,5R)-2-hydroxymethyl-3,4-dihydroxy-5-[(10S)-10,13-dihydroxy-tri decyl]pyrrolidine (1), (2R,3R,4R,5R)-2-hydroxymethyl-3,4-dihydroxy-5-[(E)9-oxo-13-hydroxy-3- tridecenyl]pyrrolidine (2), (2R,3R,4R,5R)-2-hydroxymethyl-3,4-dihydroxy-5-[(E)10-oxo-13-hydroxy-3-++ +tridecenyl]pyrrolidine (3), and (2R,3S,4R,5R)-2-hydroxymethyl-3-hydroxy-4-(beta-D-glucopyranosyloxy++ +)-5-[10-oxo-13-(beta-D-glucopyranosyloxy)tridecyl]pyrrolidine (4) respectively, by spectroscopic and chemical methods. 1-4 inhibited beta-glucosidase, beta-galactosidase and beta-mannosidase.     

Facile route to 3,5-disubstituted morpholines: enantioselective synthesis of O-protected trans-3,5-bis(hydroxymethyl)morpholines

[reaction: see text] (3R,5R)-1 R1 & R2 = TBDPS, (3S,5R)-2 R1 = Bn,R2 = TBDPS, (3S,5S)-3 R2 & R2 = Bn. trans-3,5-Bis(benzyl/tert-butyldiphenylsilyloxymethyl)morpholines, promising candidates for the C(2)-symmetric class of chiral reagents, were prepared with excellent optical purity. A key step in the synthesis is the coupling of a serinol derivative with 2,3-O-isopropylideneglycerol triflate or its equivalent. This methodology was extended to the synthesis of chiral trans-3-(benzyloxymethyl)-5-(tert-butyldiphenylsilyloxymethyl)morpholine, a potentially useful chiral building block.     

Asymmetric synthesis of the stereoisomers of 2-amino-5-carboxymethyl-cyclopentane-1-carboxylate

The stereoisomers of 2-amino-5-carboxymethyl-cyclopentane-1-carboxylate may be prepared stereoselectively from diester derivatives of (E,E)-octa-2,6-diendioc acid, with the key step utilising the conjugate addition of homochiral lithium N-benzyl-N- alpha-methylbenzylamide. The trans-C(1)-C(2)-stereoisomers are readily prepared via a diastereoselective tandem conjugate addition cyclisation protocol with lithium (R)-N-benzyl-N- alpha-methylbenzylamide, with subsequent hydrogenolysis and ester hydrolysis giving the (1R,2R,5R)- and (1R,2R,5S)- beta-amino diacids in good yields. The preparation of the cis-C(1)-C(2)-stereoisomers utilises a protocol involving N-oxidation and Cope elimination of the major diastereoisomeric product arising from conjugate addition and cyclisation, giving homochiral (R)-5-carboxymethyl-cyclopentene-1-carboxylate. Conjugate addition of either lithium (R)- or (S)-N-benzyl-N- alpha-methylbenzylamide to (R)-5-carboxymethyl-cyclopentene-1-carboxylate, and diastereoselective protonation with 2,6-di-tert-butyl phenol gives, after hydrogenolysis and ester hydrolysis, the (1S,2R,5R)- and (1R,2S,5R)- beta-amino diacids in good yield. The use of (S)-N-benzyl-N- alpha-methylbenzylamide in the initial conjugate addition and cyclisation reaction, and subsequent repetition of the elimination and conjugate addition strategy allows stereoselective access to all stereoisomers of 2-amino-5-carboxymethyl-cyclopentane-1-carboxylate.