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The sodium salt of 3β-sulfooxythornasterol A and a new glycoside — the disodium salt of 3β-sulfooxy-6α-[β-D-4-sulfooxyquinovopyranosyloxy]-5α-pregn-9(11)-en-20-one (cheliferoside LI) has been isolated from the starfishLethasterias nanimensis chelifera. The structures of the compounds have been established by spectral methods.  相似文献   

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The sodium salt of 3-sulfooxythornasterol A and a new glycoside — the disodium salt of 3-sulfooxy-6-[-D-4-sulfooxyquinovopyranosyloxy]-5-pregn-9(11)-en-20-one (cheliferoside LI) has been isolated from the starfishLethasterias nanimensis chelifera. The structures of the compounds have been established by spectral methods.Pacific Ocean Institute of Biochemistry, Far Eastern Branch, Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 520–523, July–August, 1991.  相似文献   

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A chloroform-methanol extract of the musculocutaneous sac of the Far-Eastern holothurianC. japonica has yielded a fraction of sterol sulfates (13% of the weight of the extract, 0.8% of the weight of the dry biomass), the main components of which were derivatives of cholest-5-en-3β-ol, 24-methylene-, 24-ethyl-, and 24-ethylidenecholest-5-en-3β-ols, 5α-cholestan-3β-ol, and 24-methyl- and 24-methylene-5α-cholesten-3β-ol; among the minor components were found the sulfates of 24-ethyl-5α-cholestan-3β-ol of cholesta-5,22-dien-3β-ol, of a Δ5-C30 sterol, and also of dienic and trienic C26 sterols.  相似文献   

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实验室中合成叔硫醇缺少简便方法。用叔醇和氢溴酸与硫脲直接反应是目前采用的方法。Lee和Akerstrom曾用此法合成了叔硫醇,但碳原子数没超过七个。Sprague及Kresze分别用干燥氯化氢及盐酸代替氢溴酸也合成了叔硫醇,但产率不高。本文提出了用叔醇、硫酸与硫脲反应来制备叔硫醇的方法,并合成了六个叔硫醇。  相似文献   

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A chloroform-methanol extract of the musculocutaneous sac of the Far-Eastern holothurianC. japonica has yielded a fraction of sterol sulfates (13% of the weight of the extract, 0.8% of the weight of the dry biomass), the main components of which were derivatives of cholest-5-en-3-ol, 24-methylene-, 24-ethyl-, and 24-ethylidenecholest-5-en-3-ols, 5-cholestan-3-ol, and 24-methyl- and 24-methylene-5-cholesten-3-ol; among the minor components were found the sulfates of 24-ethyl-5-cholestan-3-ol of cholesta-5,22-dien-3-ol, of a 5-C30 sterol, and also of dienic and trienic C26 sterols.Institute of Immunology, Ministry of Health of the USSR, Moscow. M. M. Shemyakin Institute of Bioorganic Chemistry, Academy of Sciences of the USSR, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 470–477, July–August, 1984.  相似文献   

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<正>Two alkyl phenols,namely,2,5-dimethoxy-3-undecylphenol(1) and 5-methoxy-3-undecylphenol(2),were isolated together with two known benzoquinones,5-O-methylembelin(3) and 2-dehydroxy-5-O-methylembelin(4) from the wood of Averrhoa carambola.Their structures were elucidated on the basis of spectroscopic methods(1D and 2D NMR).  相似文献   

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周亚利  徐京  刘宗辉  薛冰 《化学通报》2024,87(2):203-208
生物质资源替代化石资源制取燃料和化学品已成为发展可再生能源化工的重要研究方向之一。本文综述了近年来以生物质平台分子乳酸酯为原料制备丙酮酸酯的研究工作,主要涉及的反应包括气相催化反应、液相催化反应和光催化反应。详细讨论了各种类型的催化剂对反应性能的影响;最后,对乳酸酯催化转化制取丙酮酸酯的发展前景进行了展望。  相似文献   

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Chemistry of Natural Compounds - A new alkyl polyglycoside, together with two known compounds (2 and 3), was isolated from the roots of Ardisia crispa (Thunb.) A. DC. Structures of these compounds...  相似文献   

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Cellulose derivatives containing poly(oxyethylene oxide) chains in their structural units are prepared by the oxyalkylation of cellulose sulfates in the presence of an alkaline catalyst. The degrees of sulfation of oxyethylated cellulose sulfates vary from 0.8 to 2.0, and the molar substitutions with ethylene glycol residues are in the range from 3 to 10. The NMR study of the products of complete hydrolysis of the compounds of interest shows that oxyethyl groups predominantly add at second and third positions of the anhydrous glucose unit of cellulose. It is found that the oxyethylation of cellulose sulfates decreases the reduced viscosity of their aqueous solutions. The compounds under consideration exhibit inhibitory ability with respect to the blood coagulation, that is, antithrombin activity, which varies in the range 0.5 to 34.4 units/mg.  相似文献   

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Quinone pigments in the crinoids were investigated. New quinone sulfates 1 and 3 were isolated from Tropiometra afra macrodiscus and Oxycomanthus japonicus, respectively. The structures 1 and 3 were determined to be 1,6,8-trihydroxy-3-propylanthraquinone-2-carboxylic acid 6-O-sulfate (ptilometric acid 6-O-sulfate) and 2-butanoyl-3,6,8-trihydroxy-1,4-naphtoquinone 6-O-sulfate, respectively, by chemical and spectroscopic analysis. Ptilometric acid 6-O-sulfate (1) showed an antifeedant activity on fish.  相似文献   

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Abstract: Reaction of a number of alkyl halides with tetrathiomolybdate in water as the solvent affords the corresponding disulfides in good yields.  相似文献   

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By the use of TG—MS, the thermal dissociation of anhydrous CuSO4 and Al2(S04)3 was found to proceed according to the reactions:
followed by the reactions:
No SO3 was indicated in the dissociation of alunite. The sulfate ion appears to dissociate by at least two different mechanisms although the parameter which controls the mechanisms has not been elucidated.  相似文献   

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