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以对甲苯碘酸为催化剂合成(4R,5R)-2-乙基-2-(6-甲氯基-2-萘基)-1,3-二氧戊环-4,5-二羧酸二甲酯 相似文献
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Paul D. Swedenborg Richard L. Jones Hui-Qiang Zhou Injae Shin Hung-Wen Liu 《Journal of chemical ecology》1994,20(12):3373-3380
In a previous study we reported identification of (3R*,5S*,6R*)-3,5-dimethyl-6-(methylethyl)-3,4,5,6-tetrahydropyran-2-one as a component of the pheromone ofMacrocentrus grandii Goidanich. The lactone was present in male and female wasps, and laboratory and field bioassays demonstrated that both sources of the lactone elicit flight initiation, upwind anemotaxis, and casting in male wasps. In the present study, the synthetic (3R,5S,6R)- and (3S,5R,6S)-lactone enantiomers (RSR andSRS, respectively) were bioassayed for biological activity. In wind tunnel studies theSRS enantiomer elicited flight initiation, upwind anemotaxis, and casting by male wasps comparable to lactone derived from male and female wasps. Flight response to theRSR enantiomer averaged 14 percent of theSRS enantiomer. No specific ratio of the stereoisomers was found more attractive than theSRS enantiomer alone. Field studies demonstrated theSRS enantiomer was active alone in attracting male wasps. When paired with (Z)-4-tridecenal (a previously identified female-derived sex pheromone), theSRS enantiomer yielded a synergistic response comparable to (Z)-4-tridecenal plus female-derived lactone. 相似文献
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Isidoro Izquierdo Cubero Maria T. Plaza Lopez-Espinosa Anthony C. Richardson 《Journal of chemical ecology》1993,19(6):1265-1283
The synthesis of (2S,5R)-(1) and (2R,5R)-2-methyl-1,6-dioxaspiro [4.5]decane (2) from (2RS,5R,8R,9R,10S)-8,9,10-trihydroxy-2-methyl-1, 6-dioxaspiro[4.5]decane (8), obtained in five steps fromd-fructose using Wittig's methodology, reduction, and spiroketalation, has been accomplished by a Corey dideoxygenation at C-8,9, followed by a Barton deoxygenation at C-10, of the appropriately protected derivatives.Enantiospecific synthesis of spirocetals. Part V. For Part IV, see Izquierdo et al. (1992). 相似文献
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以R-( )-长叶薄荷酮为起始原料,经1,4-加成、还原、溴代、水解等4步反应合成了标题化合物,总产率77%。其结构用1HNMR、13CNMR和IR进行了表征。 相似文献
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(R)-醇腈酶催化法合成(R)-(-)-1-(2-萘基)-2-N-甲基氨基乙醇 总被引:1,自引:0,他引:1
以2-萘甲醛为原料,经酶致转氰化、氰基还原、甲酰化、酰胺还原合成了光学活性(R)-(-)-1-(2-萘基)-2-N-甲基氨基乙醇5.转氰化过程采用来源于苦杏仁、枇杷仁、桃仁、黑布林果仁和苹果籽仁的醇腈酶催化HCN对底物醛的加成获得(R)-氰醇,通过比较反应产率和产物对映体过量值(ee)发现苦杏仁醇腈酶的催化效果最好,相应值分别为68.8%和88.3%;(R)-氰醇的O-保护衍生物2经化学法转化为标题化合物5,总产率达47%,ee值达88.0%, 其结构经IR和1H-NMR确证.实验结果表明,醇腈酶催化合成的手性氰醇光学纯度较高,是合成手性氨基醇化合物的优秀原料,并且在随后的化学转化过程中各步反应产物均很好地保留了光学纯度. 相似文献
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以3,4-二氟硝基苯为原料,与吗啉在二异丙基乙胺中反应4 h得到3-氟-4-吗啉硝基苯(Ⅰ),在w(Pd)=10%催化下,Ⅰ与甲酸铵在V(THF) V(甲醇)=1 4中反应6 h,得3-氟-4-吗啉苯胺(Ⅱ),Ⅱ与光气在通入干燥HCl气体下反应得3-氟-4-吗啉异氰酸苯酯(Ⅲ),最后在无水LiBr和n-Bu3PO催化下,Ⅲ与(R)-丁酸缩水甘油酯在二甲苯中反应2 h,所得产物在甲醇钠催化下,与甲醇反应3 h,合成了(R)-3-(3-氟-4-吗啉苯基)-2-氧-5-(口恶)唑烷基甲醇(Ⅳ),总收率35.8%. 相似文献
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医药中间体(3R,4R)-3-[(1R)叔丁基二甲基硅氧乙基]-4-乙酰氧基-2-氮杂环丁酮的合成 总被引:1,自引:0,他引:1
以6-氨基青霉烷酸(6-APA)为原料经重氮化、溴化、酯化、还原、开环、氧化反应得到目标产物医药中间体(3R,4R)-3-[(1R)叔丁基二甲基硅氧乙基]-4-乙酰氧基-2-氮杂环丁酮。经1H NMR,IR证明得到了氮杂环丁酮,提高了酯化反应的收率,改变了格氏试剂反应中苛刻的条件,降低了开环反应的温度并提高了开环收率,总收率为35.88%。 相似文献
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Coleman PJ Schreier JD Cox CD Breslin MJ Whitman DB Bogusky MJ McGaughey GB Bednar RA Lemaire W Doran SM Fox SV Garson SL Gotter AL Harrell CM Reiss DR Cabalu TD Cui D Prueksaritanont T Stevens J Tannenbaum PL Ball RG Stellabott J Young SD Hartman GD Winrow CJ Renger JJ 《ChemMedChem》2012,7(3):415-24, 337
Insomnia is a common disorder that can be comorbid with other physical and psychological illnesses. Traditional management of insomnia relies on general central nervous system (CNS) suppression using GABA modulators. Many of these agents fail to meet patient needs with respect to sleep onset, maintenance, and next-day residual effects and have issues related to tolerance, memory disturbances, and balance. Orexin neuropeptides are central regulators of wakefulness, and orexin antagonism has been identified as a novel mechanism for treating insomnia with clinical proof of concept. Herein we describe the discovery of a series of α-methylpiperidine carboxamide dual orexin?1 and orexin?2 receptor (OX(1) R/OX(2) R) antagonists (DORAs). The design of these molecules was inspired by earlier work from this laboratory in understanding preferred conformational properties for potent orexin receptor binding. Minimization of 1,3-allylic strain interactions was used as a design principle to synthesize 2,5-disubstituted piperidine carboxamides with axially oriented substituents including DORA 28. DORA 28 (MK-6096) has exceptional in?vivo activity in preclinical sleep models, and has advanced into phase?II clinical trials for the treatment of insomnia. 相似文献
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以六氢苯酐为原料,采用顺反异构化反应合成反式-1,2-环己烷二甲酸;然后,选用较为廉价的R-(+)-α-甲基苄胺(R-PEA)作为拆分剂,通过手性拆分、酸化合成(1R,2R)-反式环己烷二甲酸。探讨了催化剂种类、反应温度和反应时间对产品顺反式比例的影响;同时考察了溶剂种类和用量对手性拆分效果的影响。反式-1,2-环己烷二甲酸的最优合成工艺条件为:硫酸为催化剂,反应温度120℃以上,反应时间12 h左右,在该反应条件下产品收率为80%;采用1HNMR测定了产物中反式质量分数为99.3%;最佳手性拆分条件为:甲醇作溶剂,n(反式-1,2-环己烷二甲酸)∶n(R-PEA)=1∶1,每10 g反式-1,2-环己烷二甲酸加入30 mL甲醇,在该反应条件下(1R,2R)-反式环己烷二甲酸·(R)-PEA盐的收率可达38%;经过酸化后得到(1R,2R)-反式环己烷二甲酸,酸化收率为85%;采用手性柱HPLC测定了目标产物的光学纯度(ee值)为98.48%。 相似文献
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替卡格雷是一种口服选择性小分子抗凝血药,不需要通过代谢激活,自身具有抗血小板活性。(1R,2S)-2-(3,4-二氟苯基)环丙胺是合成替卡格雷的一个关键中间体。该文在文献报道的合成路线基础上对其中关键步骤——不对称Corey-Chaykovsky环丙烷化反应进行了研究,筛选出最优反应条件:以L-薄荷醇为手性辅剂,三甲基碘化锍盐为硫叶立德试剂,二甲亚砜和四氢呋喃为混合溶剂,温度为10~12℃,质量分数10%的碘化亚铜为催化剂时,反应收率为60.5%;合成(1R,2S)-2-(3,4-二氟苯基)环丙胺5步总收率为20.0%。 相似文献
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以环戊二烯和二氯乙酰氯为原料,经环加成和Baeyer-Villiger氧化制得3,3-二氯-3,3a,6,6a-四氢-2H-环戊并[b]呋喃-2-酮(4),收率65.3%.然后经光学活性苯乙胺(PEA)拆分后,与多聚甲醛经Prins反应、粗产品不经分离,直接水解得(3aR,4S,5R,6aS)-3,3-二氯-5-羟基-4-(羟甲基)六氢-2H-环戊并[b]呋喃-2-酮(6),收率26.4%.最后用锌粉还原得(3aR,4S,5R,6aS)-5-羟基-4-(羟甲基)六氢-2H-环戊并[b]呋喃-2-酮(2),收率96.4%. 相似文献
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A convenient partial synthesis of the lactone (+)- 10 is reported starting from the readily available methyl (S)-(+)-3-hydroxy-2-methylpropanoate (+)- 1 . Furthermore, an efficient three step route to the optically active saturated isoprene unit (-)- 13 in high yield starting from the lactone (+)- 10 is reported for the first time. 相似文献
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席夫碱--(1R,2R)-N,N'-二亚水杨基-1,2-环己二胺,通常称之为手性Salen,是近年来不对称催化反应以及不对称合成中最重要和最活跃的配体之一.其合成方法一般是利用光学活性的(1R,2R)-(+)-环己二胺为原料,经与水杨醛反应得到;或者由(1R,2R)-环己二氯化铵,经NaOCH3/CH3OH中和,再与水杨醛反应得到[1]. 相似文献