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SELECTIVE REDUCTION OF 3,17—DIOXO—STEROIDS TO 17β-HYDROXY-3-OXO-STEROIDS
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作者 Qin Jian ZHAO 2hen Su LI Department of Medicinal Chemistry Beijing Medical University Beijing,100083 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第6期479-482,共4页
11β-Hydroxy-androst-4-en-3,17-dione(1a),androst-4,9(11)-dien-3,17- dione-(2a),androst-4-en-3,11,17-trione(3a),11α-methoxy-androst-4-en-3,17-dione (4a)and 11β-metboxy-androst-4-en-3,17-dione(Sa)were selectively redu... 11β-Hydroxy-androst-4-en-3,17-dione(1a),androst-4,9(11)-dien-3,17- dione-(2a),androst-4-en-3,11,17-trione(3a),11α-methoxy-androst-4-en-3,17-dione (4a)and 11β-metboxy-androst-4-en-3,17-dione(Sa)were selectively reduced to the corresponding 17β-OH derivatives in one step without the protection of 3- oxo(and 11-oxo,in the case of 3a)group with the yields ranging from 65% to 79%.In these reactions,the ditute NaBH_4(or KBH_4)solution in methanol was added dropwise to the 3,17-dioxo-steroids solution in methanol-benzene-pyridine, while the reaction mixtures were well stirred at -5~5℃.Acid(such as gtacial acetic acid)was added to quench the reactions.The resulted testosterone derivatives(1b~5b)were purified by flash chromatography. This method appties to the reduction of other 3,17-dioxo-steroids such as△~1 -3-one,△^(1.4)-3-one,△^(4.6)-3-one,△^(1.4.6)-3-one containing compounds. 展开更多
关键词 DIOXO SELECTIVE REDUCTION OF 3 17 STEROIDS TO 17 hydroxy-3-OXO-STEROIDS OCH
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The Synthesis of 4,5-Diphenyl-2-(2'-hydroxy-3'-tert-Butyl)-2-Oxazolines andTheir derivatives
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《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 1999年第S1期538-538,共1页
关键词 TERT-BUTYL The Synthesis of 4 5-Diphenyl-2 hydroxy-3 Oxazolines andTheir derivatives
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Synthesis and Characterization of Some Transition Metal Chelates of 5-(1-Hydroxy-6-Naphthylazo-3-Sodium Sulphonate) Thiobarbituric (L_1) and Barbituric (L_2) Acids
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作者 Nabil S. Youssef and K.H.Hegab(Inorganic Chemistry Department, National Research Center, Dokki., Giza, Egypt) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1999年第3期263-266,共4页
Some transition metal chelates of two ligands L1 and L2 were prepared and characterized by elemental analysis. The IR and 1H NMR spectra of several chelates of two ligands L1 and L2 showed the involvement of the azo g... Some transition metal chelates of two ligands L1 and L2 were prepared and characterized by elemental analysis. The IR and 1H NMR spectra of several chelates of two ligands L1 and L2 showed the involvement of the azo group in chelation with the transition metaI ions, in most of the studied chelates, and that the two ligands L1 and L2 showed the involvement of the azo group in chelation with the transition metal ions, in most of the studied chelates, and that the two ligands L1 and L2 were coordinated either in the enol or the keto form. IR spetra also showed that Fe(III)-, Ni(II)-, Mn(II)-, VO(II)-L1 and Cu(II)-L2 chelates behaved in a bidentate manner, in contrast with the two (1:1) M:L cobalt chelates with the two ligands are tridentate.TG analysis indicated the presence of three to twelve water molecules of hydration eliminated on heating up to 150℃ and one or two coordinated water molecules removed at 150~180℃.The octahedral structure is proposed fOr all the chelates, except Cu(II)-L2 and Ni(II)-L1 chelates which have square planar geometry, based on their electronic spectra 展开更多
关键词 III ACIDS hydroxy-6-Naphthylazo-3-Sodium Sulphonate L1 L2 Synthesis and Characterization of Some Transition Metal Chelates of 5 Thiobarbituric and Barbituric
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Synthesis and Crystal Structure of Tris(N-p-methylphenyl-3-hydroxy-2-ethyl-4-pyridinonato)iron(III)
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作者 路再生 牛德仲 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2001年第6期466-469,共4页
The complex [Fe(C14H14NO2)3]2H2O has been prepared by reaction of N-p-methylphenyl-3-hydroxy-2-ethyl-4-pyridinone with FeCl36H2O. A single-crystal X-ray study shows that the iron atoms lie in a trigonally distorted oc... The complex [Fe(C14H14NO2)3]2H2O has been prepared by reaction of N-p-methylphenyl-3-hydroxy-2-ethyl-4-pyridinone with FeCl36H2O. A single-crystal X-ray study shows that the iron atoms lie in a trigonally distorted octahedral environment coordinated to the hydroxy and ketone oxygen atoms of three ligands in the mer configuration Mr=773.57(C42H46N3O8Fe). The crystal is hexagonal with space group P31c; a=15.943(2), c=17.612(4)? V=3877.0(12)?, Z=4, Dc=1.325g/cm3, m=0.445mm-1, F(000)=1634, R=0.0446, wR= 0.1154 for 3085 reflections with I >2s(I). The bond lengths from iron to oxygens are 1.980(1)?for the ketone oxygens and 2.071(1)?for the hydroxy oxygens. The molecule exhibits the expected propeller shape, and the angle of the trigonal twist is 48.37. The dihedral angles are 0.5(2)?between chelate ring plane and pyridine ring plane and 71.31(7)?between pyridine ring plane and benzene ring plane. The solvent H2O(O(3) and O(4)) molecules are linked with O(2) and O(1) by hydrogen bonds with bond lengths 2.900(1) and 2.999(1)? respectively. 展开更多
关键词 crystal structure iron(III) complex N-p-methylphenyl-3- hydroxy-2-ethyl-4- pyridinone
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First Synthesis of (±)-3-(5-Hyd roxy-4-Methyl-7-Isopropyl-3E,7-Octadienyl)- △~2-Butenolide
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作者 Jin QU Wei Dong LI +1 位作者 Jing Ll Yu Lin LI(National Key Laboralory of Applied organic Chemistry and Institute of Organlc ChemistryLanzhcn Umversity Lanzhou 730000) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第5期411-412,共2页
An efficIent total synthesis of (±)-3-(5-hydroxy-4-methyl-7 △-butenolide, a new fi1n1esane-b;.Fed homosesquiterPeIle lactone. starting from geraniol through eightsteps are described.
关键词 First Synthesis of Li BUTENOLIDE hydroxy-4-Methyl-7-Isopropyl-3E 7-Octadienyl
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An Improved Method for the Sy nthesis of Optically Active Tomoxetines and Fluoxetines
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作者 徐成富 袁承业 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2004年第8期775-778,共4页
A chemoenzymatic approach was applied to the preparation of chiral 3-hydroxy-3-arylpropionates and 3-hydroxy-4,4,4-trifluorobutanoate that are potential precursors for certain chiral pharmaceuticals including chiral ... A chemoenzymatic approach was applied to the preparation of chiral 3-hydroxy-3-arylpropionates and 3-hydroxy-4,4,4-trifluorobutanoate that are potential precursors for certain chiral pharmaceuticals including chiral tomoxetines and fluoxetines. 展开更多
关键词 hydroxy-3-arylpropionate 3-hydroxy-4 4 4-trifluorobutanoate Candia rugosa lipase (CRL) tomoxetine FLUOXETINE
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Quinoline alkaloids isolated from Scolopendra subspinipes mutilans 被引量:2
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作者 Yan-fang Li Wu-zhan Liu +4 位作者 Jian-wei Fan Chuan-liang Huang Li-hua Deng Hui-fang Zhuang Yong-xia Guan 《Chinese Herbal Medicines》 CAS 2019年第3期344-346,共3页
Objective: To study the quinoline alkaloids from the ethanol extract of Scolopendra subspinipes mutilans(SSM).Methods: The chemical constituents were isolated and purified by macroporous resin column, medium pressure ... Objective: To study the quinoline alkaloids from the ethanol extract of Scolopendra subspinipes mutilans(SSM).Methods: The chemical constituents were isolated and purified by macroporous resin column, medium pressure preparation chromatography, and semi-preparative HPLC. Their structures were elucidated by IR,MS, and NMR experiments.Results: Three quinolone alkaloids were obtained and identified as 3-hydroxy-4-methoxyquinolin-8-yl hydrogen sulfate(1), jineol-8-sulfate(2), and jineol(3), respectively.Conclusion: Compound 1 is a new compound from SSM. 展开更多
关键词 3hydroxy-4-methoxyquinolin-8-yl hydrogen SULFATE jineol jineol-8-sulfate QUINOLINE ALKALOIDS SCOLOPENDRA subspinipes mutilans L. Koch
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