A novel synthesis of (±)-3-aminonocardicinic acid

(±)-3-Aminonocardicinic acid (3-ANA, 2), which is an important material for the synthesis of nocardicin A (1) and other biologically active analogues, has been synthesized by the application of a new method for the synthesis of α-methylene-β-lactams.     

桦木酸及其衍生物的制备与抗肿瘤作用的研究进展

桦木酸是一种羽扇豆烷型的五环三萜类化合物,因具有显著的抗肿瘤和抗HIV病毒特性而受到人们关注。桦木酸存在于多种植物中,可以用提取法得到,但由于桦木酸在植物中含量低,其主要来源是由合成法得到。许多桦木酸衍生物也具有抗肿瘤活性。本文介绍了桦木酸的提取与合成等制备方法,以及几种桦木酸衍生物的合成路线,并对桦木酸及其衍生物的抗肿瘤途径和机理进行了概述。     

Reaction of acyl derivatives of phosphorous acid with dienes

Conclusions Cyclic anhydrides, namely salicylphosphorous acid derivatives, react with conjugated dienic hydrocarbons and form phospholene derivatives, which do not contain the salicyclic acid moiety.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 6, pp. 1327–1329, June, 1971.     

Some derivatives of α-pyrone-3-carboxylic acid and its homologs

Saponification of the appropriate 3-carbethoxy-α-pyrones gives α-pyrone-3-carboxylic acid and its homologs, further converted via their acid chlorides to the substituted amides of the acids.     

Preparation of 3-bromomethyl-3-butenal diethylacetal and its conversion into isoprenoid aldehydes derivatives

The cyclopropanation of ethyl 3,3-diethoxypropionate with alkoxytitanacyclopropane reagents followed by the cleavage of the three-membered carbocycle in the formed cyclopropyl mesylate provided in a good yield 3-bromomethyl-3-butenal diethylacetal. The latter was brought into reactions of aldehyde allylation and cross-coupling with allyl halides in the intermediate stages at the generation of carbanionic intermediates. The conversion of compounds obtained into the corresponding β, γ- or α,β-unsaturated aldehydes demonstrated the opportunity of applying 3-bromomethyl-3-butenal diethylacetal as a C5-isoprenoid building block.     

Preparation of methoxysilyl humic acid derivatives with the use of 3-isocyanatopropyltrimethoxysilane

A new method for modifying (methoxysilylating) coal humic acids by reacting them with 3-isocyanatopropyltrimethoxysilane is described. The modification products structurally characterized by FTIR and NMR spectroscopy. The sorption ability of methoxysilated humic acids on silica gel is studied in the batch mode to illustrate their affinity to silicon minerals.     

Preparation and antiplatelet activity of glycidic acid derivatives

Arylalkanoic acid derivatives exhibit a variety of biological effects. In the current publication some of new glycidic acid derivatives were prepared via the Darzens condensation. The synthetic approach, analytical and spectroscopic data of all newly synthesized compounds are presented. The prepared compounds were evaluated as potential inhibitors of arachidonic acid-induced platelet aggregation and their activity was compared with that of acetylsalicylic acid as the standard. (±)-Ethyl 3-{4-[(4-methoxyphenyl)sulfanyl]phenyl}-3-methyl-cis-oxirane-2-carboxylate (IC₅₀ = 0.07 mmol L⁻¹) and (±)-3-{4-[(4-methoxyphenyl)sulfanyl]phenyl}-3-methyl-cis-oxirane-2-carboxylic acid (IC₅₀ = 0.06 mmol L⁻¹) showed the highest antiplatelet activity against arachidonic acid-induced platelet aggregation comparable with the standard. Structure-activity relationships between the chemical structure, lipophilicity, and the antiplatelet activity of the evaluated compounds are discussed.     

2-Bromohexafluoroisobutyric acid and its derivatives

Summary 2-Bromohexafluoroisobutyric acid and its derivatives were prepared.     

Photocyclization of quinopimaric acid and its derivatives

Photolysis was inverstigated of quinopimaric acid derivatives under various conditions. The structure of the photolysis products was proved with ¹H, ¹³C, and mass spectra and XRD analysis.     

Preparation of Ru(CO)3(PMe3)MeI and its acetyl derivatives

[Ru(CO)₄PMe₃] reacts with MeI to give fac-[Ru(CO)₃(PMe₃)(Me)I]. The latter reacts with PMe₃ to give a mixture of the three isomers of cis-bis(trimethylphosphine)-cis-dicarbonyl acetyl iodide [Ru(CO)₂(PMe₃)₂(COMe)I]. Decarbonylation of the mixture gives only the trans-bis(trimethylphosphine)-cis-dicarbonyl methyl iodide complex [Ru(CO)₂(PMe₃)₂MeI], which was also prepared by oxidative addition of MeI to [Ru(CO)₃(PMe₃)₂].     

3-Thiolcoumarin and its derivatives

3-Thiolcoumarin (8) and 3,3′-dithio-biscoumarin (9) were prepared. When compound (8) reacted with various Michael acceptors, some of the intermolecular primary addition products were followed by a sequential intramolecular Michael addition with ring closure forming a series of tetrahydro-thieno [2,3-c][1]benzopyran-4(H)-one derivatives (e.g. 16), the formation of which depends upon the structures of the acceptors. The stereochemistry of the tricyclic compounds was determined and discussed. The allyl thioethers of compound (8) were prepared. 3-Allyl coumarin thioether (26) was subjected to Claisen rearrangement in N, N-dimethylaniline, the expected rearranged products (27) and (28) being obtained. However, 3-cinnamyl coumarin thioether (29) under the same condition gave 3-(p-N,N-dimethylamino) thiobenzyl-coumarin (32) and other products. Phenyl cinnamyl thioether reacted similarly giving p-(N,N-dimethylamino)benzyl phenyl thioether (35).     

3-疏基香豆素及其衍生物的研究

研究了3-疏基香豆素(8)、3,3'-二硫代双香豆素的合成及8与一系列Michael受体的反应.按受体结构不同,除都能发生分子间的加成反应外,有些还可进一步发生第二次分子内的加成反应,关环后得到一系列四氢噻吩并[2,3-C][1]苯并吡喃-4(H)-酮的衍生物.对这些化合物的立体化学及结构进行了鉴定.8分别和烯丙基溴、肉桂基溴缩合,前者在N,N-二甲苯胺内发生正常的Claisen重排,得到1,2-二氢-2-甲基噻吩并[2,3-C][1]苯并吡喃-4-(H)-酮及1,2,3,5-四氢硫代吡喃并[2,3-C][1]苯并吡喃-5-酮,但后者的反应产物是3-(ρ-N,N-二甲氨基)苄硫基香豆素.     

Research on acyl isocyanates and their derivatives

1-Substituted benzimidazolinethiones, 3-substituted 1-acylbenzimidazolinethiones, and acyl thiobiurets, respectively, are formed in the reaction of acyl, alkyl, and aryl isocyanates with benzimidazolinethione, its 1-acyl derivatives, and thiourea. The IR and UV spectra of the compounds obtained are analyzed.See [1] for communication X.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 695–698, May, 1973.     

Investigations on acyl isocyanates and their derivatives

The reaction of thiourea with -halogenoacyl carbamates has given the corresponding isothiouronium salts (stable in the case of the -propionyl compound), which readily form 2-iminothiazolidin-4-one derivatives in the presence of moisture or alkalis.For Communication VI, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, Vol. 6, No. 7, pp. 908–912, July, 1970.     

Preparation of 3-substituted isocoumarins in the reactions of homophthalic anhydride and its derivatives

Acetylation of 4-nitrohomophthalic anhydride gave 4-acetyl-7-nitroisochroman-1,3-dione, which was converted to 3-methyl-7-nitroisocoumarin. 3-Benzylisocoumarin derivatives were synthesized by reaction of homophthalic anhydrides with arylacetic acids in acetic anhydride and triethylamine.Communication XXVIII from the series Condensation of Dicarboxylic Acid Anhydrides with Compounds Containing Active Methylene Groups. See [1] for communication XXVII.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1487–1489, November, 1977.