Studies towards the synthesis of (1R,2S)- and (1S,2S)-1,2-epoxy-3-hydroxypropylphosphonates and (1S,2S)- and (1R,2S)-2,3-epoxy-1-hydroxypropylphosphonates

The trans-configured fosfomycin analogue, diethyl (1S,2S)-1,2-epoxy-3-hydroxypropylphosphonate, was synthesised by the intramolecular Williamson reaction of diethyl (1S,2R)-1,3-dihydroxy-2-mesyloxypropylphosphonate. The cis-analogue was obtained as O-ethyl or O,O-diethyl (1R,2S)-1,2-epoxy-3-hydroxypropylphosphonates, when (1R,2R)-1,3-dihydroxy-2-mesyloxypropylphosphonate or its 3-O-trityl derivative were used as starting materials, respectively. The intramolecular Williamson cyclisations of diethyl (1S,2R)- and (1R,2S)-1-benzyloxy-3-hydroxy-2-mesyloxypropylphosphonates led to diethyl (1S,2S)- and (1R,2S)-2,3-epoxy-1-benzyloxypropylphosphonates, respectively, with the concomitant formation of diethyl (E)-1-benzyloxy-3-hydroxyprop-1-en-1-phosphonate. From diethyl (1S,2S)- and (1R,2S)-2,3-epoxy-1-benzyloxypropylphosphonates, enantiomerically pure diethyl (1S,2S)- and (1R,2S)-1,2-dihydroxypropylphosphonates were obtained by catalytic hydrogenation, while diethyl (1S,2S)- and (1R,2S)-3-acetamido-1,2-dihydroxypropylphosphonates were produced after epoxide ring opening with dibenzylamine, acetylation and hydrogenolysis.     

Synthesis of 2-oxazolidinones from (1S,2S)-2-amino-1-(4-nitrophenyl)-1,3-propanediol

A series of isomeric 2-oxazolidinones has been synthesized from (1S, 2S)-2-amino-1-(4-nitrophenyl)-1,3-propanediol. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 579–584, April, 2006.     

Synthesis of (S)-5-(1-aminoethyl)-2-(cyclohexylmethoxy)benzamide

Three short syntheses of the title compound, a peptidomimetic for the Glu-Glu-Ile-NH₂ portion of Ac-pTyr-Glu-Glu-Ile-NH₂, a high affinity peptide for the Src SH2 domain, are described. The most efficient route produces the title compound in a final enantiopurity of 94% ee.     

Synthesis of (-)-(S)-3-sec-butyl- and (+)-(S)-5-sec-butyl-2(1H)-pyridinone

Optically active (+)-(S)-5-sec-butyl- and (-)-(S)-3-sec-butyl-2(1H)-pyridinone are synthesized and the relationship between optical activity and minimum optical purity of the latter is determined.     

Efficient syntheses of four stable-isotope labeled (1R)-menthyl (1S,2S)-(+)-2-phenylcyclopropanecarboxylates

Many carbenoid cyclopropanation reactions promoted by chiral catalysts give product mixtures reflecting impressive diastereo- and enantioselectivities. Few provide a single chiral product efficiently. This limitation has been overcome in cyclopropanations of styrene and isotopically labeled styrenes with alpha-diazoacetates. Convenient syntheses on a 20 g scale of each of four chiral isotopically labeled (1R)-menthyl (1S,2S)-2-phenylcyclopropanecarboxylates (the 1-d-3-(13)C, 1,(3S)-d2, 1,2,(3S)-d3, and 1,3,3-d3 isotopomers) of better than 99% ee have been realized.     

(-)-(1R,2S)-肉豆蔻木脂素的不对称合成

报道了天然产物(-)-肉豆蔻木脂素的全合成. 以香草醛为起始原料, 经Wittig反应、LiAlH₄还原和Sharplass不对称双羟化等反应构建了苏式结构的中间体; 以焦性没食子酸为原料, 经Claisen重排反应制得另一种苯丙素片段; 2个中间体通过Mitsunobu反应, 缩合并使构型翻转, 得到赤式-(-)-肉豆蔻木脂素. 为赤式8-O-4′新木脂素的合成提供了一种新方法.     

Synthesis of (2S,3S)-[3-(2)H1]-4-methyleneglutamic acid and (2S,3R)-[2,3-(2)H2]-4-methyleneglutamic acid

(2S,3S)-[3-(2)H1]-4-Methyleneglutamic acid 1a and (2S,3R)-[2,3-(2)H2]-4-methyleneglutamic acid 1b have been synthesised for use in biosynthetic and metabolic studies.     

(2S)-(+)-2-溴-1-(6'-甲氧基-2'-萘基)丙-1-酮的不对称合成

以(2R,3R)-酒石酸二甲酯为手性辅助剂,6-甲氧基-2-丙酰基萘经缩酮化、溴化铜不对称溴化、水解等反应合成了(2S)-2-溴-1-(6'-甲氧基-2'-萘基)丙-1-酮。总收率94%。     

Regioselectivity in the reaction of paraformaldehyde with (1S,2S)-2-aryl(hetaryl)methylamino-1-(4-nitrophenyl)-1,3-propanediols

The reaction of paraformaldehyde with (1S,2S)-2-aryl(hetaryl)methylamino-1-(4-nitrophenyl)-1,3-propanediols produces a mixture of isomeric 3-aryl(hetaryl)methyl-4-hydroxymethyl-5-(4-nitrophenyl)- and 3-aryl(hetary)methyl-4-hydroxy(4-nitrophenyl)methyloxazolidines and is reversible. Université d'Auvergne, Faculté de Farmacie, 28, Place Henri Dunant, Clermont-Ferrand, France. Samara State University, Samara 443011, Russia. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 536–541, April, 1999.