梨圆蚧性信息素3,7-二甲基-2,7-辛二烯-1-醇丙酸酯的合成

Gieselmann等鉴定出梨圆蚧性信息素的主要组分为(Z)-3,7-二甲基-2,7-辛二烯-1-醇丙酸酯(1_a)及相应的E-体(1_b)。     

用异戊二烯的催化调聚反应合成梨圆蚧性信息素组份

梨圆蚧Quadraspidiotus perniciosus是世界性的农业害虫,主要危害苹果、梨树等果树.Gieselmann和Anderson等分离并鉴定出梨圆蚧性信息素为3,7-二甲基-2,7-辛二烯-1-醇丙酸酯(1)和7-甲基-3-亚甲基-7-辛二烯-1-醇丙酸酯(2).1的Z体和E体的比例约为10:1.田间生测发现.1的Z体、E体对雄性蚧虫均有强烈的引诱活性,两者以不同比例混合使用,活性并无明显的降低.     

合成梨圆蚧性信息素主要组分的新路线

3,7-二甲基-2,7-辛二烯-1-醇丙酸酯(1)是梨圆蚧性信息素的主要组分。报道的以乙酰乙酸乙酯和丙烯酸乙酯为原料的合成工作,路线太长。考虑到化合物(1)具有1,5-二羰基化合物的碳骨架,我们合成了2,6-庚二酮(2),并通过单保护及两步Wittig反应合成了化合物(1),合成路线如下:     

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     

梨圆蚧性信息素的合成

(Z)和(E)-3，7-二甲基-2，7-辛二烯-1-醇丙酸酯(3a，3b)是梨圆蚧(Quadraspidlotus perniciosus，Comstock)性信息素的主要组分，田间试验表明，3a、3b单独使用或以不同比咧混合使用，生物活性没有明显差别。我们利     

用聚合物试剂合成梨圆蚧性信息素的主要成分

梨园蚧Quadraspidiotus Perniciosus的主要成分为3,7-二甲基-2,7-辛二烯-1-醇丙酸酯(1a,1b).Anderson等、Alderdice等、Novak等及陈家威、张合胜等报道过用溶液法进行合成。我们利用聚合物试剂进行了固相合成,该方法具有可进行选择性反应、工艺简单、产率高等优点。     

(2S,3R,7R/S)-3,7-二甲基-2-十三碳醇丙酸酯的全合成研究进展

靖远松叶蜂(Diprion jingyuanensis)是危害油松的一种叶蜂,其性信息素的活性成分为(2S,3R,7R/S)-3,7-二甲基-2-十三碳醇丙酸酯。本文根据C9+C6路径、C10+C5途径和其他路径对(2S,3R,7R/S)-3,7-二甲基-2-十三碳醇丙酸酯及其关键中间体的合成研究进行了综述。参考文献60篇。     

不同种兰花香气成分分析

利用固相微萃取和气相色谱-质谱联用(GC-MS)技术分析了5种兰花的香气成分。结果表明,5种兰花香气成分的种类和含量存在明显差异。绿苹果(Den.LittleGreen Apples)主要由反-2-己烯醛、己醛、丁羟甲苯、乙酸乙酯和3-己烯-1-醇等化合物构成,其中乙酸乙酯和反-2-己烯醛可能是花朵中苹果香的主要来源。香水文心兰(Onc.Sharry Baby)的主要香气化合物是顺-3,7-二甲基-1,3,6-辛三烯、3,7-二甲基-2,6-辛二烯-1-醇和3,7-二甲基-1,6-辛二烯-3-醇,三者的相对含量总和为84.57%。台北小姐(Cym.Miss Taipei)香气成分的主要特征不明显,除4-甲基苯酚和2-乙基丁醛外,其他化合物的相对含量均低于5%。夕阳红(Phal.Taida Salu)有香气成分50种,相对含量为87.01%,主要成分为柯巴烯、正己烷、甲酸己酯和3-己烯-1-醇。绿世界(Blc.Sung Ya Green‘green world’)有香气成分37种,主要由丙基环丙烷、2-(4-甲氧基苯基)乙醇、反-2-己烯-1-醇、3-己烯-1-醇、反-2-己烯醛、丁基呋喃和3,7,11-三甲基-1,6,10-十二碳三烯-3-醇等组成。     

7,8,7'''',8''''-四氢番茄红素的合成

以金合欢醇为起始原料,制备了金合欢基季磷盐(3);3与2,7-二甲基-2,4,6-辛三烯-1,8-二醛发生双分子Wittig反应合成了7,8,7′,8′-四氢番茄红素,总产率64.2%.其结构经UV,1H NMR,IR和MS表征.     

由谷氨酸合成具有光学活性的齿小蠹二烯醇

齿小蠹二烯醇(Ipsdienol,2-甲基-6-甲叉基-2,7-辛二烯-4-醇,1)是手性昆虫信息素.S( )对映体,它首次从齿小蠹(Ips paraconfusus Lanier)的粪便中分离出来.后来又发现其它种小蠹虫的信息素也含有这种成份.R(-)齿小蠹二烯醇是另外一种齿小蠹(Ips pini)信息素的主要组份.Mori,Ohloff 等报道三种方法合成光学活性的齿小蠹二烯醇.所用手性原料为 R( )甘油醛缩丙酮、R( )羟基丁二酸及( )或(-)马鞭烯酮(verbenone).     

A novel method for spectrophotometric determination of pregabalin in pure form and in capsules

Background

Dihydrolinalool and terpineol are sources of fragrances that provide a unique volatile terpenoid alcohol of low toxicity and thus are widely used in the perfumery industry, in folk medicine, and in aromatherapy. They are important chemical constituents of the essential oil of many plants. Previous studies have concerned the biotransformation of limonene by Pseudomonas putida. The objective of this research was to study biotransformation of myrcene by Pseudomonas aeruginosa. The culture preparation was done using such variables as different microbial methods and incubation periods to obtain maximum cells of P. aeruginosa for myrcene biotransformation.

Results

It was found that myrcene was converted to dihydrolinalool and 2,6-dimethyloctane in high percentages. The biotransformation products were identified by Fourier-transform infrared spectroscopy (FT-IR), ultraviolet (UV) analysis, gas chromatography (GC), and gas chromatography-mass spectroscopy (GC-MS). Comparison of the different incubation times showed that 3 days was more effective, the major products being 2,6-dimethyloctane (90.0%) and α-terpineol (7.7%) and comprising 97.7%. In contrast, the main compounds derived for an incubation time of 1.5 days were dihydrolinalool (79.5%) and 2,6-dimethyloctane (9.3%), with a total yield of 88.8%.     

Reductive transformation of isoprenoid cyclosulfonates into linear homoallylic alcohols and amines

Conclusions Isoprene, myrcene, and ocimene sultones were converted into the corresponding linear homoallylic alcohols and amines via the stage of desulfonylation of the in situ generated allylsulfinic acids. A new synthesis of myrcenol and isogeraniol has been carried out.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1820–1823, August, 1985.     

叶绿素光敏氧化香叶烯合成齿小蠹二烯醇

报道了以叶绿素(Chl)为敏化剂、香叶烯光敏氧化的同时用四丁基硼氢化铵(TBABH₄)还原得到相应的二级和三级烯丙基醇。讨论了玫瑰红(RB)、甲素(HA)和叶绿素三种敏化剂对产物分布的影响。实验结果表明:以叶绿素为敏化剂由香叶烯合成的齿小蠹二烯醇(Ipsdienol,2-甲基-6-甲叉基-2,7-辛二烯-4-醇),副产物少,收率较高。还讨论了还原剂的用量及光照时间对产物的影响。     

Epoxides from Myrcene: Selective Obtention

1,2-and 3,10-epoxy myrcene are selectively obtained from dihydroxy derivatives prepared by an oxidation reaction of myrcene with potassium permanganate.     

Efficient Syntheses of New 2,2′-Disubstituted-2,3-dihydrofuran Derivatives and Natural Polyketide Analogues

Efficient syntheses of new 2,2′-disubstituted-2,3-dihydrofuran(5H)-4-one,spiro{benzofuran-2,2′-bicyclo[2.2.1]heptan}-4(5H)-one derivatives, and natural polyketide analogues have been achieved via the oxidative [3 + 2] cycloaddition of 1,3-dicarbonyl compounds with monoterpenes myrcene, camphene, and natural phenyl propenes, namely anethole and safrole respectively. Interestingly, the reaction of isoprene and myrcene with 1,3-dicarbonyl compounds yielded 2,2-disubstituted tetrahydrobenzofuran-4(5H)-one derivatives at room temperature. Thus, several substituted 2,3-dihydrofuran derivatives (3a–3h) with potential biological activity have been synthesized.     

Soil and Leaf Nutrients Drivers on the Chemical Composition of the Essential Oil of Siparuna muricata (Ruiz & Pav.) A. DC. from Ecuador

Chemical compositions of plants are affected by the initial nutrient contents in the soil and climatic conditions; thus, we analyzed for the first time the effects of soil and leaf nutrients on the compositions of the essential oils (EOs) of Siparuna muricata in four different localities in Ecuador. EOs were obtained by hydrodistillation and analyzed by gas chromatography/mass spectrometry (GC/MS) and a gas chromatography/flame ionization detector (GC/FID). Enantiomeric distribution by GC/MS was determined, modifying the enantiomeric separation of β-pinene, limonene, δ-elemene, β-bourbonene, cis-cadina-1 (6), 4-diene and atractylone. A total of 44 compounds were identified. The most representative for L1 were guaiol, atractylone and 4-diene; for L2, cis-cadina-1(6),4-diene and myrcene; for L3, atractylone, myrcene and germacrene B; and finally, L4 germacrene B, myrcene and cis-cadina-1(6),4-diene. Correlations between soil- leaf chemical elements such as Al, Ca, Fe, Mg, Mn, N and Si in the different localities were significant with chemical composition of the essential oil of Siparuna muricata; however, correlations between soil and leaf K, P, and Na were not significant. Cluster and NMDS analysis showed high dissimilarity values of secondary metabolites between four localities related with changes in soil- leaf nutrients. Thus, the SIMPER routine revealed that not all secondary metabolites contribute equally to establishing the differences in the four localities, and the largest contributions are due to differences in guaiol, cis-cadina-1(6),4-diene, atractylone and germacrene. Our investigation showed for the first time the influences of altitude and soil- leaf chemical elements in the chemical composition of the EOs of S. muricata.     

2-hydroxymethyl-4-phenylthio-1-butene as a key compound for total synthesis of acyclic terpenoids

A new total synthesis of myrcene, citral, squalane, and isophytol employing 2-hydroxymethyl-4-phenylthio-1-butene as a starting material is described.     

Cyclodimerisation reactions of conjugated dienes with aldehydes—I: Formation of tetrahydropyrans and their 300 MHz 1H NMR spectra

The palladium catalysed reaction of butadiene with aldehydes yields 2-substituted 3,6-divinyl-tetrahydropyrans.^1–4 The reaction has been extended to isoprene and myrcene. With formaldehyde only 2,5-substituted pyrans have been isolated. The isomeric tetrahydropyrans obtained were fully characterised by ¹H NMR, and representative 300 MHz spectra are given. Attempts to react aldehydes with 2-methoxybutadiene were unsuccessful.     

Chemo‐ and stereoselective polymerization of 3‐methylenehepta‐1,6‐Diene and Its thiol‐ene modification

Here we report on the coordination polymerization of a vinyl‐functionalized butadiene monomer, 3‐methylenehepta‐1,6‐diene (MHD) with exclusive conjugated diene chemoselectivity, high 1,2‐regioselectivity and moderate isotacticity (1,2‐selectivity > 99%, mm triad = 93%). Random copolymers of MHD and other conjugated diene (isoprene or myrcene) are also synthesized. The pendent vinyl groups of MHD homo or copolymers could be quantitatively converted into various functional groups via thiol‐ene click reaction. The resulting functionalized polybutadiene‐based material display versatile thermal and surface properties. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 1031–1039     

Production of vibrationally excited OH in chemiluminescent reactions of ozone with monoterpenes

Emission from vibrationally excited OH molecules (Meinel bands) has been observed in chemiluminescent gas-phase reactions of ozone with myrcene, α-phellandrene, α-pinene, limonene and linallol. In addition emission from HCHO(¹A₂) and methylglyoxal(³A_u) has also been identified in reactions with myrcene, α-pinene and α-phellandrene.