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1.
Crown ether derivatives have been extensively developed to provide enhanced structural recognition of substrate alkyl-ammonium cations. In particular a number of investigations of complexation of chiral alkylammonium salts by chiral crown ethers have been reported. The enantioselectivity has been applied in the chromatographic resolution of amino acid perchlorates. In general the crown ethers used in these studies have been based upon derivatives of 2, 2′-dihydroxy-1, 1′-binaphthyl1 or deriv…  相似文献   

2.
CompoundI',anovelmonoterpenoid,wasisolatedfromMulisiaspinosa(Compositae).Thestructureofl,determinedbyspectroscopictechniques,correspondedto3,7dimethyl-3-acetoxy-6-hydroxy-cotl,7-diene(thenameof6-hydroxy-7(9)-dehydro-6,7dihydronerylacetateinreferenceIisuncorrect).HowevertheabsoluteconfigurationsatC-3andC-6werenotdetermined.CompoundIwassynthesizedbyphotooxidationoflinalylacetate=,howevertheauthorsobtainedtheisomermixtureof1.Hereinwereportthetotalsynthesisof(3S,6S)-( )-1fromgeraniol2throughsi…  相似文献   

3.
l,7-Bis(4-hydroxyphenyl)-3-hydroxy-1,3-heptadien-5-oneIIwagfirstlyisolatedfromtheseedsofAIPiniablepharocalyxK.Schum.(Zingiberaceae)asanoveldiarylheptanoid.Meanwhile,l,7-his(4-hydroxyphenyl)-3-hydroxy-l,3,6-heptatTien-5-one2,aknowndiarylheptanoid,wasisolatedaswell.Therecentpublication'reportedthatIstronglyinhibitedtheaggregationofplateletinducedbycollagen,arachidonicacidandadenosinediphosphate.AdditionalresearchZprovedthat2couldactasaninhibitoroftheHIV-1integrase.Byourfindings,thesynthesi…  相似文献   

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1,2-二(3-甲氧基-4-羟基苯基)乙烷(1,2-Bis(4-hydroxy-3-methoxyphenyl)ethane),又名亚乙基双愈创木酚(Ethylenediguaiacol),双香兰素(Divanillyl),结构如图1中副产物.较早的报道[1,2,3]是从原木素降解得到,具有抗氧化及抗肿瘤作用[4].  相似文献   

6.
Conclusion 1,7-Bis(4-aminophenylamido)- and l,7-bis(4-aminophenylcarboxy)-m-carboranes were prepared and characterized.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2786–2787, December, 1986.  相似文献   

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A new cinnamide derivative,(E)-1-(4-(bis(4-methoxyphenyl)methyl)piperazin-1-yl)-3-(4-acetoxy-3-methoxyphenyl)prop-2-en-1-one(C31H34N2O6,Mr = 530.60),has been synthesized by the condensation of 1-(bis(4-methoxyphenyl)methyl)piperazine and(E)-3-(4-acetoxy-3-methoxyphenyl)acrylic acid.The compound was characterized by 1H NMR,13 C NMR,H RMS and single-crystal X-ray diffraction.The crystal belongs to the orthorhombic system,space group P212121 with a = 24.946(5),b = 7.6380(15),c = 14.555(3) ?,V = 2773.3(10) ?3,Z = 4,Dc = 1.271 g/cm3,F(000) = 1128,μ = 0.088 mm-1,Mo Kα radiation(λ = 0.71073 ?),the final R = 0.0641 and w R = 0.1170.A total of 3009 unique reflections were collected,of which 1760 with I 2σ(I) were observed.Intramolecular C(17)–H(17B)···O(3) and C(22)–H(22A)···O(3) interactions as well as intermolecular C(27)–H(27A)···O(3) hydrogen bonds help to stabilize the crystal structure.The title compound was evaluated for the anti-ischemic activity in vitro and in vivo.The bioassay results indicated that the title compound displayed efficient activities against glutamine-induced neurotoxicity in PC12 cells and significantly prolonged the survival time of mice subjected to acute cerebral ischemia.  相似文献   

9.
包可婷  张伟  李英霞  胡春 《合成化学》2016,24(4):355-358
报道了一条合成(3S,4S)-4-氨基-3-羟基-5-苯基戊酸(Ahppa)衍生物的新路线。以氨基保护的L-苯丙氨酸为起始原料,依次经Weinreb胺缩合、还原、aldol缩合及溴仿4步反应合成了3个Ahppa衍生物,总收率5.8%~6.7%,其结构经1H NMR, 13C NMR和ESI-MS确证。对反应条件进行了探讨,结果表明:催化剂D-脯氨酸用量对反应收率影响不大,对立体选择性影响较大;氨基上保护基体积较大有利于提高反应立体选择性。  相似文献   

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采用1,3-偶极环加成反应合成了2-甲基-3-对甲氧基苯基-5-间甲氧基苯基异噁唑啉,分离了顺、反异构体,采用核磁共振氢谱分析表征了顺反异构体的谱图行为,对异构体的生物活性进行了测定,新杀菌剂2-甲基-3-对甲氧基苯基-5-间甲氧基苯基异噁唑啉对病菌的有效成分为反式结构,顺式体为无效成分.  相似文献   

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以D-酒石酸二乙酯和芳香醛为原料,经缩醛化、氨解两步反应合成了15个未见文献报道的适合工业化生产庚铂类似物的关键中间体——2-芳基-(4S,5S)-4,5-双(胺甲酰基)-1,3-二氧戊环,产率49%~70%,其结构经1HNMR和MS表征。  相似文献   

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《Tetrahedron: Asymmetry》2007,18(20):2454-2461
A facile method for the preparation of tert-butyl (3R,5S)-6-hydroxy-3,5-O-isopropylidene-3,5-dihydroxyhexanoate is described by a chemoenzymatic approach. In this method, one hydroxyl stereocenter at C5 is obtained with a high ee value (up to 98.0%) via an enzymatic transesterification resolution of l-chloro-3-(4-methylbenzyloxy)-2-propanol. The other hydroxyl stereocenter at C3 was built with 98.0% de, by acid-hydrolysis of a 1,3-diol-acetonide syn/anti-10. It is noteworthy that the reduction of β-hydroxy ketone 8 with sodium borohydride can be carried out smoothly in aqueous isopropyl alcohol with a high diastereomeric ratio syn/anti (drs:a) of 4.0:1.  相似文献   

16.

Abstract  

Sodium-hydroxide-catalyzed condensation of di-p-methyl- and di-p-methoxybenzil with acetone derivatives was investigated in methanol. Di- and trisubstituted products were obtained as cyclopentenones, while tetraaryl-substituted systems were isolated as cyclopentadienones. The structures of the products were identified by elemental analysis, infrared (IR), nuclear magnetic resonance (1H NMR), and mass spectroscopy. The solid-state structure of 4-hydroxy-3,4-bis(4-methoxyphenyl)-5,5-dimethyl-2-cyclopenten-1-one was further studied by single-crystal X-ray diffraction analysis. The title compound crystallizes in an orthorhombic space group and intermolecular O–H···O and C–H···O hydrogen bonds stabilize the crystal lattice.  相似文献   

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4-甲氧基苯甲酰肼与芳醛反应得到相应的酰腙(2),2与乙酸酐脱水环化合成了标题化合物,其结构经1H NMR,IR,MS和元素分析表征。  相似文献   

19.
The two diarylheptanoids (E)-1-(4'-hydroxy-3'-methoxyphenyl)-7-(4"-hydroxyphenyl) hept-4-en-3-one 1 (Gingerenone C) and (±)-5-hydroxy-1-(4'-hydroxy-3'-methoxyphenyl)-7-(4"-hydroxyphenyl)-3-heptanone 2 were synthesized from vanillin 3 and 4-hydroxybenzaldehyde 9.  相似文献   

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