Modified synthesis of methyl (1R,2R,3E,5R)-3-(hydroxyimino)-5-methyl-2-(1-methylethyl)-cyclohexanecarboxylate from (R)-4-menthen-3-one

A modified stereospecific synthesis of potentially biologically and pharmacologically active methyl (1R,2R,3E,5R)-3-(hydroxyimino)-5-methyl-2-(1-methylethyl)cyclohexanecarboxylate from (R)-4-menthen-3-one was developed using sequential 1,4-conjugate addition of Norman reagent catalyzed by CuI?CBF₃?Et₂O?CCuCl₂ and ozonolysis?Creduction of the intermediate (R,R,R)-vinylmenthone by hydroxylamine hydrochloridein MeOH.     

Reaction of 2-(1-methyl-2-butenyl)anilines with polyphosphoric acid

Conclusions Cyclization of 2-(1-methyl-2-butenyl)anilines in polyphosphoric acid proceeds with isomerization of the side chain and leads to indolines and indanes in high yields.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 839–842, April, 1985.     

Synthesis of chalcones bearing 2-hydroperoxy-3-methyl-3-butenyl or 2-hydroxy-3-methyl-3-butenyl group from prenylated chalcones

Abstract

Chalcones bearing 2-hydroperoxy-3-methyl-3-butenyl or 2-hydroxy-3-methyl-3-butenyl groups, such as xanthoangelol E (1a), xanthoangelol D (2a), psorachalcone A (2?b), xanthohumol D (2c), and related derivatives were first synthesized by using the ene reaction of prenylated chalcones with singlet oxygen.     

Asymmetric synthesis of 5-(1-hydroxyalkyl)-5-methyl-5H-furan-2-ones

The reactivity of 5-methyl-4-(pyrrolidin-1-yl)-5H-furan-2-one with aldehydes and with acyl chlorides followed by reduction was studied. The aldol condensation gave predominantly the anti aldol product when the acylation-reduction sequence led exclusively to the syn product. The use of a chiral pyrrolidine, (S)-2-methoxymethylpyrrolidine (SMP), allowed the synthesis of enantio-enriched compounds, the acylation-reduction leading to the (R,R) addition product.     

2-甲基-6-(3-甲基-2-丁烯基)对苯二醌的合成

以邻甲基苯酚为原料,与1-氯-2-甲基-2-丁烯反应生成2-甲基-6-(3-甲基-2-丁烯基)苯酚,然后催化氧化得到目标产物2-甲基-6-(3-甲基-2-丁烯基)对苯二醌。该合成路线简单,易于操作,最终收率51%。     

Synthesis and properties of 1-methyl-2-phenyl-5-(2-furyl)- and 1-methyl-2-phenyl-5-(2-thienyl)imidazoles

2-Phenyl-5-(2-furyl)- and 2-phenyl-5-(2-thienyl)imidazoles were synthesized by condensation of 2-furoylmethyl and 2-thenoylmethyl acetates with benzaldehyde under the conditions of Weidenhagen reaction. The products were converted to N-methyl derivatives in the KOH-acetone system. The electrophilic substitution reactions of the products (acylation, bromination, nitration, sulfonation, hydroxymethylation) were studied.     

“一锅串联法”合成2-[(E)-2-2-氯-1-甲基-3-吲哚基)乙烯基]喹啉-3-羧酸(英文)

设计了以2-(溴甲基)喹啉-3-甲酸乙酯(4)与2-氯-1-甲基-3-吲哚醛(5)为起始化合物,通过简便有效的"一锅法"反应,首次将吲哚环引入2-苯乙烯基喹啉骨架模型,从而得到一新颖结构的双杂环化合物,即(E)-2-(2-(2-氯-1-甲基-1H-3-吲哚基)乙烯基)喹啉-3-羧酸(3),其结构通过波谱数据和元素分析得以证实。     

Cyclization of 1,3-disubstituted 2-(3-butenyl)-2-cyclohexen-1-ols

The cationic cyclization of cyclohexenols 8a-c gave mixtures of the octalinols 9a-c and 10a-c with 9a-c as main products. By cyclization of the isomeric educts 13a-c, the same products were formed in different proportions.     

Synthesis of 2-amino-3-benzyl-5-(p-hydroxyphenyl)pyrazine

2-Amino-3-benzyl-5-(p-hydroxyphenyl)pyrazine (2), a precursor of Watasenia preluciferin (coelenterazine) (1), is widely distributed in marine bioluminescent animals. It was prepared from p-hydroxyphenylglyoxal aldoxime (5) in two steps; by condensation with or-aminophenylpropiononitrile in the presence of TiCl4 in pyridine, followed by reduction of the resulting N-oxide (6) with Zn-AcOH in CH2Cl2 and produced 2, with an 89% overall yield. This procedure was linked with the facile one-step preluciferin synthesis reported in the previous paper. Thus, Watasenia preluciferin (1), frequently required for various chemiluminescent and bioluminescent studies, was coveniently synthesized in three steps from 5, with a 56% overall yield, overcoming the difficulty of obtaining it from natural sources.     

三七中2-(1'''',2'''',3'''',4''''-四羟基丁基)-6-(2",3",4"-三羟基丁基)-吡嗪的分离、鉴定及药理活性研究

从三七水溶性成分中首次分离得到一个多羟基吡嗪衍生物 .该化合物经 MS,NMR,1 H-1 H COSY,1 3 C-1 H COSY和 HMBC等鉴定其结构为 2 -( 1 ,2 ,3 ,4 -四羟基丁基 ) -6 -( 2 ",3",4 "-三羟基丁基 ) -吡嗪 .对该分离样品进行了合成对照和药理活性研究