2-羟基-5-甲基-5-(4-甲基戊烯-3-)基四氢呋喃的合成

本文研究了一类羰基化合物-酮类为原始料(选用了来源丰富, 价格低廉的6-甲基-5-庚烯酮-2), 经格氏反应水解, 环化及醚化即合成了2-羟基-5-(4-甲基戊烯-3-)基四氢呋喃。     

D-脯氨酸催化的(3S,4S)-4-氨基-3-羟基-5-苯基戊酸衍生物的合成

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。     

Synthesis of diarylheptanoids, (5S)-5-acetoxy-1,7-bis(4-hydroxy-3-methoxyphenyl)-3-heptanone and (3S,5S)-3,5-diacetoxy-1,7-bis(4-hydroxy-3-methoxyphenyl)heptane

The total syntheses of the first examples of diarylheptanoid natural products (5S)-5-acetoxy-1,7-bis(4-hydroxy-3-methoxyphenyl)-3-heptanone 1, and (3S,5S)-3,5-diacetoxy-1,7-bis(4-hydroxy-3-methoxyphenyl)heptane 2 isolated from the rhizomes of Zingiber officinale were accomplished using Sharpless epoxidation and cross-metathesis reactions as the key steps.     

3－氨基－4－硝基苯甲酸的合成

以苯甲酸为原料，经硝化、还原、乙酰化、再硝化、水解，制备了标题化合物，结果较好。     

Synthesis of 2,2-dimethyl-5-hydroxy-3-(3-oxobutyl)-7-pentyl-4-chromone

Alkylation and deformylation of 2,2-dimethyl-3-hydroxymethylene-5-hydroxy-7-pentyl-4-chromone occurs in the same step to give the title compound.     

Modification of Synthesis of 3-Chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone(MX)

Addition of chlorine to methyl 3-(dichloromethyl)-4,4-dichlorocrotonate (1), a critical procedure in the total synthesis of the title compound MX, was modified by using novel catalysts. A minor modification in the purification of MX was also described.     

Molecular structure of 2,4-diacetyl-3-(2-chlorophenyl)-5-hydroxy-5-methyl-N-(4-methylphenyl)-1-cyclohexenylamine

The molecular structure of 2,4-diacetyl-3-(2-chlorophenyl)-5-hydroxy-5-methyl-N-(4-methylphenyl)-1-cyclohexenylamine (Ia) determined by X-ray diffractometry (XRD) is described. Two intramolecular hydrogen bonds: O-H…O=C and N-H…O=C are realized in molecule Ia.     

Synthesis of 4-Acyl-5-aryl-3-hydroxy-1-(3-picolyl)-3-pyrroline-2-ones

Russian Journal of General Chemistry - Reaction of methyl esters of acylpyruvic acids with a mixture of aromatic aldehyde and 3-picolylamine gave...     

Synthesis of 1,6-dihydro-5-hydroxy-6-oxo-3-(trifluoromethyl)-4-pyridazinecarboxylates

The reaction of 2-(alkylamino)-3-(trifluoroacetyl)butenedioates 2a-b with alkyl and aryl hydrazines in ether provides 1,6-dihydro-6-oxo-3-(trifluoromethyl)-4-pyridazinecarboxylates as their alkylamine salts 3a-g . The structures of these products are substantiated using 2D nmr and ¹⁵N nmr techniques.     

5-(4-氯苯基)-1-(2,4-二氯苯基)-4-甲基吡唑-3-羧酸的合成

对氯苯丙酮经三甲基氯硅烷保护后与草酸单乙酯单酰氯缩合制得4-(4-氯苯基)-3-甲基-2,4-二氧代丁酸乙酯(4);4与2,4-二氯苯肼盐酸盐缩合成腙、再经分子内环合、水解合成了制备利莫那班的关键中间体——5-(4-氯苯基)-1-(2,4-二氯苯基)-4-甲基吡唑-3-羧酸,总收率30.3%,其结构经1HNMR和MS确证。     

Rearrangement of 5-hydroxy-1-(4-tolyl)-4-N-methylcarbamoyl-1,2,3-triazole to 5-hydroxy-1-methyl-4-N-(4-tolyl)-carbamoyl-1,2,3-triazole

Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, p. 2875, December, 1989.     

Reactions of 5-aryl-4-acyl-1-(4-hydroxyphenyl)-3-hydroxy-3-pyrrolin-2-ones with arylamines

The reaction of 5-(4-chlorophenyl)-4-benzoyl-1-(4-hydroxyphenyl)-3-hydroxy-3-pyrrolin-2-one with aromatic amines affords the corresponding 3-arylamino derivatives, and the reactions of 5-aryl-4-acetyl-1-(4-hydroxyphenyl)-3-hydroxy-3-pyrrolin-2-ones with p-toluidine yield 5-aryl-4-(1-p-tolylamino)ethylene-1-(4-hydroxyphenyl)pyrrolidin-2,3-diones.