梨小食心虫性信息素顺-8-十二碳烯-1-醇乙酸酯及其反式异构体的合成

梨小食心虫(Grapholitha molesta Busck)是一种世界性的梨、桃、苹果等果树害虫.此虫在我国分布甚广.1969年Roelofs等鉴定其性信息素的结构为顺-8-十二碳烯-1-醇乙酸酯(1)^[1],其后报道1与少量反-8-十二碳烯-1-醇乙酸酯(2)合用,则引诱活性可以增强^[2].     

从中国南海软珊瑚中分离的环氧西松烯天然产物的结构更正

(- ) - 7,8- Epoxycembrene- C[( - ) - 7,8- ECC,1 ]是 Bowden等 [1] 于 1 980年首次从澳大利亚软珊瑚Sarcophyton crassocaule中分离得到的新的环氧西松烯 .其化学结构经光谱数据证实为 ( 1 E,3E,1 1 E) -1 -异丙基 - 4,8,1 2 -三甲基 - 7,8-环氧 - 1 ,3,1 1 -十四碳环三烯 ,但 C- 7,C- 8位环氧的立体化学未被确定 . Shin等 [2 ] 也从未鉴定属名的加勒比海域的软珊瑚 Eunicea sp.中分离得到过该天然产物 . 1 997年 ,饶志刚等 [3] 报道了从中国南海肉芝软珊瑚 ( Sarcophyton molle)中分离得到一环氧西松烯天然产物 ,确定其结构为天然…     

酶促酮酸酯还原合成(S)-2乙酰氧基十三烷

Bartelt等 [1] 于 1 989年首次从穆勒果蝇 (Drosophila mulleric)的雄性成虫体内分离出其聚集信息素 ,并确证其主要生物活性的成分为 (S) -构型的 2 -乙酰氧基十三烷 (1 ) ,而 (R) -构型无生物活性 .1 999年Hillbur等 [2 ,3 ] 发现碗豆瘿蚊 (Contarinia pisi)的雌性性信息素主要成分中也含有 (1 ) ,其对碗豆瘿蚊雄虫具有很强的性引诱作用 .有关 (1 )的合成报道较多的为酶促反应合成法 [4～ 7] .我们曾以 1 -苯砜基 - 2 -丙酮为原料经酶促还原反应合成了目标产物 ,此法尽管合成路线短 ,光学产率较高 ,但反应原料不易购得 ,且使用两摩尔比…     

用硅胶担载三氯化铁催化氧化偶联2-萘酚制备(±)2,2′-二羟基-1,1′-联萘

2,2′-二羟基 - 1 ,1′-联萘 ,由于存在受阻 C- C键轴 ,可通过拆分获得对映体纯手性双膦配体BINAP的前体 [1] ,或经不对称氧化转化成催化剂前体 [2 ] ,或用作手性试剂 ,近年来备受人们的重视 .其常用制备方法多以 Fe3 、 Mn3 及 Cu2 氧化 2 -萘酚 .尤以 Fe3 [3～ 5] 为氧化剂制备 (± ) 2 ,2′-二羟基 -1 ,1′-联萘最为经济 .传统上以甲醇 /水 ( 1 /1 ,体积比 )为介质 ,用 Fe Cl3 氧化 2 -萘酚制 (± ) 2 ,2′-二羟基 - 1 ,1′-联萘 ,产率不太高 [5] .近年来 ,Toda等 [5]利用固态反应及超声波制备此化合物 ,收率明显提高 ,但…     

双氮桥联1,10-菲咯啉大环与金属离子的配位反应研究

双氮桥联 1 ,1 0 -菲咯啉大环 H2 HAPP(图 1 )是类卟啉大环配体 .1 972年 ,Ogawa等 [1] 首次报道了　Fig.1　 Molecular structure of aza-bridged bis-phenan-throline macrocycle( H2 HAPP)该大环的合成 ,其钴、镍和铜配合物的制备也已见报道 [1～ 7] .研究结果显示 ,H2 HAPP的金属配合物可以作为人工 DNA裂解酶 [8,9] 和催化 CO2 还原的催化剂 [10 ] .由于 H2 HAPP合成产率低 ,难溶于大多数溶剂 ,因而在过去几十年中对于这类大环化合物的研究并未引起人们的广泛注意 .虽然 Ogawa等 [2 ]曾报道 ,在热的 H2 HAPP硝基苯溶液回…     

“一锅法”合成6-苯氧（苯硫）甲基-[1，3]二氧戊环并[4，5-g]喹啉-7-羧酸

以6-溴甲基-[1,3]二氧戊环并[4,5-g]喹啉-7-羧酸乙酯和酚(或硫酚)为原料,首次采用一锅法高收率地合成了6-苯氧(苯硫)甲基-[1,3]-氧戊环并[4,5-g]喹啉-7-羧酸,其结构经1H NMR,IR和元素分析表征.     

梨圆蚧性信息素主要组分——3,7-二甲基-2,7-辛二烯-1-醇丙酸酯的合成

梨圆蚧,Quadraspidiotus Perniciosus(Comstock)是世界性的农业害虫,分布甚广,主要危害苹果、梨,也危害海棠、桃、李、杏、枣和山楂等多种果树.我国东北、西北、华东、华南及西南等省均发现危害. Gieselmann等鉴定出梨圆蚧性信息素的主要组分为(z)和(E)-3,7-二甲基-2,7-辛二烯-1-醇丙酸酯(1a,1b).田间生测发现1a和1b单独使用对雄性蚧虫都有强烈的引诱活性,两者以不同比例混合使用活性不降低.Anderson等和Alderdice等已     

新型碱性离子液体催化剂高效催化合成吡喃酮[2,3-d]嘧啶酮和[2,3-d]嘧啶衍生物

制备了碱性离子液体1,1'-(丁烷-1,4-二基)双(1,4-二氮杂二环[2.2.2]辛烷-1-ium)羟化物,并采用红外光谱、1H核磁共振谱和pH值分析对其进行了表征.然后将它用于室温研磨条件下高效催化合成吡喃酮[2,3-d]嘧啶酮和[2,3-d]嘧啶.该法步骤简单,反应时间短,产物收率高,无需柱色谱分离,原料易得,且可回收利用.     

新型异核双阳离子型磺酸功能化离子液体的合成及其催化活性

合成了三种基于1-吗啉基-3-咪唑基丙烷异核双阳离子的新型二磺酸功能化BrΦsted酸性离子液体:1-[4-(4-磺酸丁基)吗啉基-3-[3-(4-磺酸丁基)咪唑基]丙烷二(三氟甲烷磺酸)盐{A,[(C4SO3H)m(C4SO3H)i]p(OTf)2}、1-[4-(4-磺酸丁基)吗啉基-3-[3-(4-磺酸丁基)咪唑基]丙烷二硫酸氢盐{B,[(C4SO3H)m(C4SO3H)i]p(HSO4)2}及1-[4-(4-磺酸丁基)吗啉基-3-[3-(4-磺酸丁基)咪唑基]丙烷二磷酸二氢盐{C,[(C4SO3H)m(C4SO3H)i]p(H2PO4)2}.其结构经FT-IR、MS、NMR等确认.选择吗啉、甲基咪唑单磺酸功能化离子液体作为对照组,以苯甲醛与环己酮之间的交叉Aldol缩合反应考察了其催化活性.用Hammett方法测定了其酸性,实验结果表明,所合成的三种双磺酸功能化离子液体的催化能力比单磺酸功能化离子液体的强,其酸性次序与催化活性相一致.其中,阴离子为三氟甲烷磺酸根的离子液体对18种Aldol缩合反应底物有极好的适应性,并且催化活性最强,产率高达90%,在重复使用10次后,仍保持较高的反应活性.关键词二磺酸功能化离子液体;合成;催化活性;Hammett方法;交叉Aldol缩合反应;重复使用     

树脂吸附层析法分离喜树果中的喜果甙

自 1 96 6年 Wall等 [1] 首次从喜树植物中分离出喜树碱后 ,至今已有 2 0多种化学成分从中分离出来 ,包括喜树碱 (Camptothecine,CPT)、 1 0 -羟基喜树碱、 1 1 -羟基喜树碱、 1 0 -甲氧基喜树碱、喜树次碱、白桦脂酸及喜果甙 (Vincoside- lactam,VCS- LT)等 [2 ] .研究表明 ,喜树碱类化合物和喜果甙均具有抗癌活性 [3～ 5] .从喜树果中分离喜果甙对充分利用我国丰富的喜树资源具有重要意义 .目前文献报道的分离提取喜果甙方法主要是溶剂萃取和氧化铝柱层析法 [6] ,过程复杂 ,收率很低 .本文采用树脂吸附法对喜果甙进行分离纯化 ,再经…     

己二烯基烯丙基醚的Wittigσ迁移重排反应

烯丙基醚类的[2.3]Wittig σ迁移重排反应是近几年来新发展的一个有机合成反应。由于此反应具有高度的非对映选择性和立体选择性,它为合成中的碳链延伸、立体选择性反应及不对称合成提供了一个新的方法,因为此反应可通过选择底物的几何构型和取代基得到立体选择性产物。[2.3]Wittig σ迁移重排     

松毛虫性信息素(5Z,7E)-十二碳二烯醇的立体选择性合成

从简单原料乙炔出发,通过炔对丙烯醛的加成反应得到7-溴代-(4Z,6E)-庚二烯醛,再经乙二醇保护、Pd催化偶联、水解、Wittig反应和还原等步骤,立体选择性地得到松毛虫性信息素(5Z,7E)-十二碳二烯醇,其结构通过IR,NMR和MS等技术得到确认.     

Practical Syntheses of Some Insect Sex Pheromones, 10- and 12-Alken-1-ol Acetates

Some insect sex pheromones 10-dodecen-1-ol acetates 5a(Z/E) and 12-tetradecen-1-ol acetates 5b(Z/E) have been synthesized from cis-13-docosenoic acid la and cis-15-tetracosenoic acid Ib via the isomerization of key intermediates 11-dodecen-1-ol acetate 4a and 13-tetradodecen-1-ol acetate 4b.     

亚洲玉米螟性信息素的简便合成

从Z-15-二十四碳烯酸(1)出发, 经关键中间体13-十四碳烯-1-醇醋酸酯(4)。以CoCl2-Ph3P-NaBH4为催化体系异构化合成亚洲玉米螟性信息素Z/E-12-十四碳烯-1-醇醋酸酯(5)。经GC测定, 其Z、E比例接近1:1。     

(Z)-1-三苯基锡基-3-对氯苯基-1-丁烯-3-醇及其卤代物的合成、表征和晶体结构

在氮气保护下,3-对氯苯基-1-丁炔-3-醇与三苯基氢化锡进行游离基加成反应,获得加成物(Z)-1-三苯基锡基-3-对氯苯基-1-丁烯-3-醇(1).加成物(1)与卤素反应后,与锡原子相连的苯基被取代,得到一卤代、二卤代和混合二卤代物(2-8).通过元素分析、¹HNMR和IR表征了化合物1～8的结构,并测定了加成物(1)、一溴代物(3)和二溴代物(5)的晶体结构.在加成物(1)的晶体结构中存在一对对映体,由于分子内存在较弱的O→Sn配位作用,构成以锡原子为中心的扭曲四面体构型.在化合物3和5分子中,存在分子内O→Sn配位键,构成以锡为中心的扭曲三角双锥构型.该系列化合物分子内的O→Sn配位能力和Lewis酸性强弱的顺序为:二卤化物>一卤化物>加成物;氯代物>溴代物>碘代物.     

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.     

Gas-phase reactions of NO3 and N2O5 with (Z)-hex-4-en-1-ol, (Z)-hex-3-en-1-ol ('leaf alcohol'), (E)-hex-3-en-1-ol, (Z)-hex-2-en-1-ol and (E)-hex-2-en-1-ol

The night-time atmospheric chemistry of the biogenic volatile organic compounds (Z)-hex-4-en-1-ol, (Z)-hex-3-en-1-ol ('leaf alcohol'), (E)-hex-3-en-1-ol, (Z)-hex-2-en-1-ol and (E)-hex-2-en-1-ol, has been studied at room temperature. Rate coefficients for reactions of the nitrate radical (NO(3)) with these stress-induced plant emissions were measured using the discharge-flow technique. We employed off-axis continuous-wave cavity-enhanced absorption spectroscopy (CEAS) for the detection of NO(3), which enabled us to work in excess of the hexenol compounds over NO(3). The rate coefficients determined were (2.93 +/- 0.58) x 10(-13) cm(3) molecule(-1) s(-1), (2.67 +/- 0.42) x 10(-13) cm(3) molecule(-1) s(-1), (4.43 +/- 0.91) x 10(-13) cm(3) molecule(-1) s(-1), (1.56 +/- 0.24) x 10(-13) cm(3) molecule(-1) s(-1), and (1.30 +/- 0.24) x 10(-13) cm(3) molecule(-1) s(-1) for (Z)-hex-4-en-1-ol, (Z)-hex-3-en-1-ol, (E)-hex-3-en-1-ol, (Z)-hex-2-en-1-ol and (E)-hex-2-en-1-ol. The rate coefficient for the reaction of NO(3) with (Z)-hex-3-en-1-ol agrees with the single published determination of the rate coefficient using a relative method. The other rate coefficients have not been measured before and are compared to estimated values. Relative-rate studies were also performed, but required modification of the standard technique because N(2)O(5) (used as the source of NO(3)) itself reacts with the hexenols. We used varying excesses of NO(2) to determine simultaneously rate coefficients for reactions of NO(3) and N(2)O(5) with (E)-hex-3-en-1-ol of (5.2 +/- 1.8) x 10(-13) cm(3) molecule(-1) s(-1) and (3.1 +/- 2.3) x 10(-18) cm(3) molecule(-1) s(-1). Our new determinations suggest atmospheric lifetimes with respect to NO(3)-initiated oxidation of roughly 1-4 h for the hexenols, comparable with lifetimes estimated for the atmospheric degradation by OH and shorter lifetimes than for attack by O(3). Recent measurements of [N(2)O(5)] suggest that the gas-phase reactions of N(2)O(5) with unsaturated alcohols will not be of importance under usual atmospheric conditions, but they certainly can be in laboratory systems when determining rate coefficients.     

Synthesis and NMR Characterization of (Z,Z,Z,Z,E,E,ω)-Heptaprenol

We describe a practical, multigram synthesis of (2Z,6Z,10Z,14Z,18E,22E)-3,7,11,15,19,23,27-heptamethyl-2,6,10,14,18,22,26-octacosaheptaen-1-ol [(Z(4),E(2),ω)-heptaprenol, 4] using the nerol-derived sulfone 8 as the key intermediate. Sulfone 8 is prepared by the literature route and is converted in five additional steps (18% yield from 8) to (Z(4),E(2),ω)-heptaprenol 4. The use of Eu(hfc)(3) as an NMR shift reagent not only enabled confirmation of the structure and stereochemistry of 4, but further enabled the structural assignment to a major side product from a failed synthetic connection. The availability by this synthesis of (Z(4),E(2),ω)-heptaprenol 4 in gram quantities will enable preparative access to key reagents for the study of the biosynthesis of the bacterial cell envelope.     

Chemical constituents of Melicope ptelefolia

Phytochemical investigations on the methanolic extract of Melicope ptelefolia Champ ex Benth. resulted in the isolation of three new compounds, identified as 3beta-stigmast-5-en-3-ol butyl tridecanedioate (melicoester) (1), (2Z, 6Z, 10Z, 14Z, 18Z, 22Z, 26E)-3', 7', 11', 15', 19', 23', 27', 31'-octamethyldotriaconta-2, 6, 10, 14, 18, 22, 26, 30-octadecanoate (melicopeprenoate) (2) and p-O-geranyl-7"-acetoxy coumaric acid (3). The compounds were isolated along with twenty-one other known compounds, lupeol (4), oleanolic acid (5), kokusaginine (6) genistein (7), p-O-geranyl coumaric acid (8), 4-stigmasten-3-one (9), 3beta-hydroxystigma-5-en-7-one (10) cis-phytyl palmitate (11), dodecane, dodecan-1-ol, ceryl alcohol, hentriacontanoic acid, eicosane, n-amyl alcohol, caprylic alcohol, octatriacontane, nonatriacontane, hexatriencontan-1-ol, methyl octacosanoate, beta-sitosterol, beta-sitosterol glucoside. Structures of all the compounds were established on the basis of MS and 1D and 2D NMR spectral data, as well as comparison with reported data.