环氧化—6—豆甾酮的合成

以豆甾醇为原料，经Ａ／Ｂ环结构改造，所得双键化合和的用过苯甲酸氧化，可高选择性，高产率地合成出２ａ，３ａ－二乙酰基－２２Ｒ－环氧－６－豆甾酮和２ａ，３ａ－环氧－２２Ｒ，２３Ｒ－环氧－６－豆甾酮，由此二化合物可较方便地制得２ａ，３ａ，２２Ｒ，２３Ｒ－甲乙酰基－６－豆甾酮。     

α－羰基烯酮环二硫代缩醛化学XXI：β，β－1，3－亚丙二硫基－α，β－不饱和酮与胍的缩合反应

在乙醇为溶剂，乙醇钠为碱的条件下，标题类化合物归１ａ～ｃ，３ａ，４ａ与胍缩合反应生成相应的嘧啶类化合物２ａ～ｃ，３ｂ，３ｃ，４ｂ。在以ＤＭＦ为溶剂，乙醇钠为碱的条件下，化合物与胍反应可生成２－氨基－４－二甲氨基－６－苯基嘧啶２ａ’。该缩合反应的特点为标题类化合物与肌缩合生成嘧啶类化合物的同时，将乙氧基或二甲氨基引入嘧啶环的确定位置。为新的嘧啶类化合物。     

1,4—二氢Hantzsch吡啶衍生物的合成及其^1H NMR和荧光 …

报道了Ｎ－甲基－４－芳基－２,６－二甲基－３,５－二乙基－１,４－二氢吡啶（２ａ－２ｆ）,４芳基－２,６－二苯基－３,５－二乙酯基－１,４－二氢吡啶（３ａ－３ｆ）及其相应的Ｎ－甲基化合物（４ａ－４ｆ）的合成（芳基ｐ－ＲＣ６Ｈ４－;Ｒ＝ＯＣＨ３,ＣＨ３,Ｈ,Ｃｌ,ＣＮ,ＮＯ２）,化合物４－芳基２,６－二甲基－３,５－二乙酯基－１,４－二氢吡啶（１ａ－１ｆ）可发射较强的荧光,化合物３呈现较弱的荥光,它     

混合三烃基锡有机酸酯化合物构效关系 （Ⅰ）二环己基－甲基－2，4－二溴－β－甲基苯氧乙酸锡酯 及二环己基－甲基－2－甲氧基－4－丙烯基苯氧乙酸锡酯的晶体结构和分子结构

报道２，４－Ｂｒ２Ｃ６Ｈ３ＯＣＨ（ＣＮ３）ＣＯ２Ｓｎ（Ｃ６Ｈ１１）２ＣＵ３（１）和２－ＯＣＨ３－４－ＣＨ３ＣＨ＝ＣＨＣ６Ｈ３ＯＣＨ２ＣＯ２Ｓｎ（Ｃ６Ｈ１１）２ＣＨ３（Ｈ２Ｏ）（Ⅱ）的晶体结构和分子结构。（Ⅰ）单斜晶系，空间群Ｐ２１／ｃ，ａ＝１３．０６７（３），ｂ＝１０．５９４（３），ｃ＝１８．１５７（４），β＝１０６．９９（２）°，Ｚ＝４，Ｄｃ＝１．６７２ｇ／ｃｍ３，Ｖ＝２４０３．７３，μ＝４３．７３１ｃｍ－１，Ｍｒ＝６２２．９９，Ｆ（０００）＝１２３２；（Ⅱ）单斜晶系，空间群Ｐ２１／ｎ，ａ＝１０．４０９（１），ｂ＝　１２．５７０（２），ｃ＝２０．６６４（２），β＝８３．５１（１）°，Ｚ＝４，Ｄｃ＝１．２８１ｇ／ｃｍ３，Ｖ＝２６８６．４Ａ３，μ＝９．７６１ｃｍ－１，Ｍｒ＝５３９．２８，Ｆ（０００）＝１１２０．最后的偏离因子，化合物（Ⅰ）Ｒ＝０．０４６，Ｒω＝０．０４６；化合物（Ⅱ）Ｒ＝０．０４９，Ｒω＝０．０４７。晶体结构解析表明，化合物（Ⅰ）和（Ⅱ）中的锡均被配体的３个碳和２个氧原子配位，配位原子呈畸变三角双锥构型；化合物中的环己基均为椅式构象；化合物（Ⅱ）中，配位水分子和另一分子的羰基氧与芳环上的甲基氧?     

2－芳酰氨基－5－（5－苯基－2H－四唑2－甲基）－1，3，4－噻二唑类化合物的合成

在浓硫酸作用下，由５－（５－苯基－２Ｈ四唑－２－乙酰基）－４－芳酰氨基硫脲１ａ～ｎ制得了一系列新的２－芳酰氨基－５－（５－苯基－２Ｈ－四唑－２－甲基）－１，３，４－噻二唑化合物（２ａ～ｎ）。所有化合物的结构均经元素分析、ＭＳ分析，部分代表化合物经ＩＲ、￣ＨＮＭＲ分析确证；初步观察了２ａ～ｎ在１％浓度下对大肠杆菌（Ｇ￣－）的抑制作用，发现２ｄ，２ｅ，２ｆ，２ｎ显示出较强的活性。     

不对称1,3,2—苯并二氧碳杂环己烷非对映消旋体的合成及生 …

通过相转移催化关环反应合成了新的６－取代－２－硫－２－烷（芳）氧－４（２，４－二氯苯基）－４－氢－１，３，２－苯并二氧磷杂环己烷（３ａ－３ｇ），用结晶法分离得到了７对非对映消旋体，其结构经ＨＮＭＲ、＾３１ＰＮＭＲ和元素分析确证，化合物３ａ－Ａ单晶Ｘ射线分析表明其构型为（２Ｒ，４Ｓ；２Ｓ，４Ｒ），生物活性测定结果表明，化合物３ｃ有良好的杀虫活性，非对映消旋体Ａ和Ｂ具有协同杀虫作用。     

2－硫代磷酸酯基－3，4－二氢呋喃并喹啉化合物的合成和抑菌活性

６－取代基－２－氧－３，４－二氢呋喃并喹啉类化合物用氢化钠还原所生成的醇钠与硫代磷酰氯缩合制备３，４－二氢呋喃并喹啉化合物，通过￣１ＨＮＭＲ，ＭＳ和元素分析鉴定了它们的结构，并初步测试了它们的抑菌活性．     

糖苷合成研究Ⅴ．2－O－烷基－5－氟脲嘧啶－O－葡萄糖醛酸苷的合成及其抗肿瘤活性研究

合成了十三个未见文献报道的２－Ｏ－烷基－５－氟脲嘧啶－Ｏ－葡萄糖醛酸甲酯（酰胺）苷类化合物，其结构经ＩＲ，￣１ＨＮＭＲ和元素分析证实。其小化合物５ａ和６ａ经初步生物学试验证明，具有较高的抑瘤活性。     

吲哚［2，3－a］喹嗪生物碱的合成及立体化学研究

各种１－［２－（３－吲哚）乙基］－哌啶烯体系可由不同的还原方法和改良的Ｐｏｌｏｎｏｖｓｋｉ反应制备，最终经质子催化环合生成所需的吲跺［２，３－ａ］喹嗪生物碱；３－乙酞基－１，４，６，７，１２，１２ｂ－六氢吲哚［２，３－ａ］喹嗪是该类生物碱及氧吲哚生物碱全合成中重要的中间体，它可进行一系列重要化学反应，最终转化为相关天然产物；产物的立体化学可通过ＮＭＲ、ＩＲ或２Ｄ－ＮＭＲ谱加以确定。     

α—羰基烯酮环二硫代缩醛化学：XXI：β,β—1,3—亚丙二硫基—α,β—不饱和酮？

在乙醇为溶剂，乙醇钠为碱的条件下，标题类化合物１ａ～ｃ，３ａ，４ａ与胍缩合反应生成相应的嘧啶类化合物２ａ～ｃ，３ｂ，３ｃ，４ｂ。在以ＤＭＦ为溶剂，乙醇钠为碱的条件下，化合物１ａ与胍反应可生成２－氨基－４－二甲氨基－６－苯基嘧啶２ａ，该缩反应的特点为标题类化合物与胍缩合生成嘧啶类化合物的同时，将乙氧基或二甲氨基引入嘧啶环的确定位置，２ａ，２ａ，３ｂ，３ｃ，４ｂ为新的嘧啶在化合物。     

Four new steroid constituents from the waste residue of fibre separation from Agave americana leaves

Three new steroidal saponins, named agamenosides H-J (1-3), and a new cholestane steroid agavegenin D (4) were isolated from the waste residue of fibre separation from Agave americana leaves, together with six known steroids. Structures of the new compounds 1-4 were deduced to be (22S,23S,24R,25S)-24-[(beta-D-glucopyranosyl)oxy]-5alpha-spirostane-3beta,6alpha,23-triol 6-O-beta-D-glucopyranoside (1), (22S,23S,24R,25S)-5alpha-spirostane-3beta,23,24-triol 24-O-beta-D-glucopyranoside (2), (22S,23S,25R,26S)-23,26-epoxy-5alpha-furostane-3beta,22,26-triol 26-O-beta-D-glucopyranoside (3), and (22S,25S)-5alpha-cholestane-3beta,16beta,22,26-tetrol (4), respectively, by means of spectroscopic analysis, including extensive 1D and 2D NMR data, and the results of hydrolytic cleavage.     

Two new polyporusterones isolated from the sclerotia of Polyporus umbellatus

In the course of searching for marker components, two new polyporusterones were isolated from the sclerotia of Polyporus umbellatus, together with another three known analogs. The structures of the new ones were elucidated as (20S,22R,24R)-16,22-epoxy-3beta,14alpha,23beta,25-tetrahydroxyergost-7-en-6-one (1) and (23R,24R,25R)-23,26-epoxy-3beta,14alpha,21alpha,22alpha-tetrahydroxyergost-7-en-6-one (2) by chemical and spectroscopic means, including HR-FAB-MS, 1D- and 2D-NMR.     

Two new epoxysteroids from Helianthus tuberosus

Two new epoxy steroids, 5α,8α-epidioxy-22β,23β-epoxyergosta-6-en-3β-ol (1) and 5α,8α-epidioxy-22α,23α-epoxyergosta-6-en-3β-ol (2), and ten known steroids including (24R)-5α,8α-epidioxyergosta-6-en-3β-ol (3), (22E,24R)-5α,8α-epidioxyergosta-6,22-dien-3β-ol (4), (22E,24R)-5α,8α-epidioxyergosta-6,9(11),22-trien-3β-ol (5), β-sitosterol (6), sitost-5-en-3β-ol acetate (7), 7α-hydroxysitosterol (8), schleicheol 2 (9), (24R)-24-ethyl-5α-cholestane-3β,5α,6β-triol (10), 7α-hydroxystigmasterol (11), and stigmasterol (12) were isolated from Helianthus tuberosus grown in Laizhou salinized land of coastal zone of Bohai Sea, China. The structures of these compounds were unambiguously established by 1D, 2D NMR and mass spectroscopic techniques. The new compounds 1 and 2 exhibited weak antibacterial activity and no antifungal activity.     

Three cycloartane glycosides from Cimicifuga rhizome and their immunosuppressive activities in mouse allogeneic mixed lymphocyte reaction

One known (1) and two new cycloartane triglycosides, 20S,22R,23S,24R-16beta,23;22,25-diepoxy-cycloartane-3beta,23,24-triol 3-O-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranosyl-(1-->2)-beta-D-xylopyranoside (2) and 20S,22R,23S,24R-16beta,23;22,25-diepoxy-cycloartane-3beta,23,24-triol 3-O-(6-O-trans-isoferuloyl-beta-D-glucopyranosyl)-(1-->2)-beta-D-glucopyranosyl-(1-->2)-beta-D-xylopyranoside (3), were isolated from a commercial Cimicifuga Rhizome. Their structures were determined by two dimensional (2D) NMR spectroscopic analysis and chemical evidence. These compounds suppressed the proliferation of lymphocytes in mouse allogeneic mixed lymphocyte reaction.     

A New Stereoselective Synthesis of Phosphiranes

The synthesis of phosphiranes from primary phosphines and diol ditosylates was found to be stereoselective, and chiral phosphiranes were prepared from optically pure diols. The four optical isomers of 1-mesityl-2,3-dimethylphosphirane, (2S,3S)-(+)-3, (2R,3R)-(-)-4, anti-cis-(meso)-5, and syn-cis-(meso)-6, were all synthesized from mesitylphosphine and the corresponding diol ditosylates. Compound 6 was unstable, but compounds 3, 4, and 5 were all isolated in pure form. Their structure assignments were based on the NMR coupling constants J(P-H) and J(P-C). The phosphiranes were transformed into tungsten pentacarbonyl complexes. Tungsten tetracarbonyl-triphenylphosphine complexes (22, 23, 24) of compounds 3, 4, and 5 were synthesized in high yields by the reaction of the phosphiranes and W(CO)(4)(PPh(3))(THF). The absolute stereochemistry of the phosphiranes 3, 4, and 5 was determined by X-ray crystal structure analysis of compounds 22, 23, and 24. Stereochemical effects on NMR coupling constants and mass spectra of the phosphiranes are discussed.     

Structures of two new steroidal glycosides, soladulcosides A and B from Solanum dulcamara

The structures of two new steroidal glycosides named soladulcosides A and B, isolated from the aerial parts of Solanum dulcamara including new sapogenols, were elucidated as (22R, 25R)-3 beta, 15 alpha, 23 alpha-trihydroxy-5 alpha-spirostan-26-one 3-O-alpha-L-rhamnopyranosyl-(1----2)-beta-D-glucopyranoside and (22R, 25R)-3 beta,23 alpha-dihydroxy-5 alpha-spirostan-26-one 3-O-alpha-L-rhamnopyranosyl-(1----2)-[alpha-L-rhamnopyranosyl-(1----4)]- beta-D-glucopyranoside, respectively.     

Castasterone,a new phytosterol with plant-hormone potency,from chestnut insect gall

A sterol which has strong potency to inclinate rice lamina was isolated from the insect gall of the chestnut tree. The structure was determined to be (22R, 23R, 24S)-2α, 3α, 22, 23-tetrahydroxy-24-methyl-5α-cholestan-6-one ($\text{1}$).     

A new pyrrolidine derivative and steroids from an algicolous Gibberella zeae strain

A new pyrrolidine derivative, 3-hydroxy-5-(hydroxymethyl)-4-(4'-hydroxyphenoxy)pyrrolidin-2-one (1), and eight known steroids, (22E,24R)-7beta,8beta-epoxy-3beta,5alpha,9alpha-trihydroxyergosta-22-en-6-one (2, a reassigned structure of (22E,24R)-5alpha,6alpha-epoxy-3beta,8beta,14alpha-trihydroxyergosta-22-en-7-one), (22E,24R)-3beta,5alpha,9alpha-trihydroxyergosta-7,22-dien-6-one (3), (22E,24R)-3beta,5alpha-dihydroxyergosta-7,22-dien-6-one (4), (22E,24R)-ergosta-7,22-dien-3beta/,5alpha,6beta-triol (5), (22E,24R)-ergosta-5,22-dien-3beta-ol (6), (22E,24R)-5alpha,8alpha-epidioxyergosta-6,22-dien-3beta-ol (7), (22E,24R)-5alpha,8alpha-epidioxyergosta-6,9(11),22-trien-3beta-ol (8), and (22E,24R)-1(10 --> 6)-abeo-ergosta-5,7,9,22-tetraen-3alpha-ol (9), were isolated from the cultures of Gibberella zeae, an endophytic fungus isolated from the marine green alga Codium fragile. Their structures and relative stereochemistry were elucidated by 1D, 2D NMR and mass spectroscopic techniques. Compound 1 showed cytotoxicity against A-549 and BEL-7402 cell lines.     

New steroidal alkaloids from Fritillaria imperialis and their cholinesterase inhibiting activities

Two new cevanine steroidal alkaloids, impericine (1) and forticine (2) along with known bases delavine (3), persicanidine A (4), and imperialine (5) were isolated from the bulbs of Fritillaria imperialis. The structures of impericine (1) [(20R,22S,25S)-5alpha-cevanin-23-ene-3beta,6beta,16beta-triol] and forticine (2) [(20S,22S,25S)-5alpha-cevanine-3beta,6beta-diol] were determined with the help of spectroscopic studies. These steroidal bases showed anti-acetylcholinesterase and anti-butyrylcholinesterase inhibitory activity.     

Molecular dynamics and NMR analysis of the configurational 13C assignment of epimeric 22,23-epoxides of stigmasterol

The determination of the stereochemistry of brasinosteroid analogs with 22,23-epoxide groups can be easily achieved by means of (13)C NMR spectroscopy. Here, we provide a rationalization of the (13)C chemical shift pattern found in 22R,23R- and 22S,23S-epoxides of stigmasterol, based on the analysis of gamma effects. (22S,23S)- and (22R,23R)-3beta-acetoxystigmast-22,23-epoxy-5,6beta-diol were used in the study as model compounds. Our methodology starts with a conformational search by means of molecular dynamics and NMR (NOE contacts) spectroscopy, which is followed by the analysis of the different gamma interactions affecting the chemical shift of interest. We demonstrate that the differences between the (13)C chemical shift patterns of 22R,23R and 22S,23S isomers arise from gamma effects as the result of diverging local conformations around the C17-C20 and C20-C22 bonds.