Ana Calvo-Mateo

3'-C-cyano-3'-deoxythymidine

3′-C-Cyano-3′-deoxythimidine (2) has been synthesized in 8 steps from 1-(β-D-ribofuranosyl)-thymine (3). 3 Was transformed to the corresponding 3′-ketonucleoside 5, which by addition of HCN followed by deoxygenation of the 2′-OH and 3′-OH groups of the resulting cyanohydrin gave 2.

Novel aldol-type cyclocondensation of O-mesyl (methylsulphonyl) cyanohydrins. Application to the stereospecific synthesis of branched-chain sugars

Reaction of O-mesylcyanohydrins of furanos-3-uloses with base afforded furanose-3-spiro-5′-[4′-amino-1′,2′-oxathiole-2′,2′-dioxide] derivatives, which on treatment with MeONa/MeOH gave C-[(E)-2-(methoxysulphonyl)-1-(amino)-vinyl] branched-chain sugars, having the same configuration as the starting cyanohydrins.

Cyanosugars III : The reaction of trimethylsilyl cyanide with keto, epoxy and acetal derivatives of carbohydrates

Abstract Reaction of methyl 2-acetamido-4,6- O -benzylidene-2-deoxy-α- D - ribo -hexopyranosid-3-ulose with Me3SiCN afforded methyl 2-acetamido-4,6- O -benzylidene-3- C -cyano-2-deoxy-3- O -trimethylsilyl-α- D - allo - Reaction of ethyl 4,6-di- O -acetyl-2,3-anhydro-α- D -mannopyranoside with Me3SiCN gave the corresponding ethyl 4,6-di- O -acetyl-2- C -cyano-2-deoxy-α- D -glucopyranoside. Reaction of methyl 4,6- O -benzylidene-2,3-anhydro-α- D -allopyranoside or methyl 4,6- O -benzylidene-2,3-di- O -tosyl-α- D -glucopyranoside with Me3SiCN at - 75° or - 50° gave the corresponding methyl 6- O -[(R)-cyano phenyl methyl]-α- D -glyco-pyranosides with high or total regio and stereoselectivity.

Synthesis of 2-Amino-3-C-(Carboxymethyl)-2,3-Dideoxy-Allopyranose Derivatives

Abstract The Wittig reaction of methyl 2-acetamido-4,6-O-benzylidene-2-deoxy-α-d-ribo-hexopyranosid-3-ulose witethoxycarbonylmethylenetriphenylphosphorane afforded the corresponding 3-C-(E)-ethoxycarbonyle-thyiene-3-deoxy glycoside 3. Catalytic hydrogenation of 3 (Pd/C) gave stereoselectively, after removal of benzylidene and ethyl ester protecting groups, methyl 2-acetamido-3-C-carboxymethyl-2,3-dideoxy-α-D-allo-hexopyranoside (11).

Synthesis of 3-Deoxy Derivatives of 2-Amino-2-Deoxy-D-Glucose

Abstract Methyl 2-acetamido-2, 3-dideoxy-α-d-glucopyranosides have ceen obtained by an elimination reaction of the corresponding 3-O-mesylallopyranoside with NaH or DBU follcwed by hydrogenation over Pd/C. Reaction of 2-acetaido-2-deoxy-3-O-mesylallopyranosides with inorganic azides under phase transfer reaction conditions afforded 2-acetamido-3-azido-2, 3-dideoxy-gluccyranoses which after hydrogenation over Pd/C gave 2-acetamido-3-amino-2,3-dideoxy-D-glucopyranoses.

Aldol reaction of reducing sugars. Convenient stereoselective synthesis of ribofuranosylacetone and chiral dienones

Aldol reaction of 2,3-O-isopropylidene-D-ribose with acetone, catalysed by aqueous K2CO3, gave 1(2,3-O-isopropylidene-α-D-ribofuranosyl)acetone. Similar reactions of 2,3,5-tri-O-benzyl-D-ribofuranose, 2,3,4,6-tetra-O-benzyl-D-gluco- and -D-galactopyranose afforded chiral (3E,5Z,7S)-octa 3,5-dien-2-one, (3E,5Z,7S,8R)-nona-3,5-dien-2-one, and (3E,5Z,7R,8R)-nona-3,5-dien-2-one derivatives, respectively.

Stereoselective Synthesis of 3-C-Branched-Chain Sugars by Aldol Reaction of Furanos-3-Uloses with Acetone

Abstract Aldol reaction of 1,2-O-isopropylidene-5-O-tertbutyl-dimethylsilyl-α-D-erythro-pentofuranos-3-ulose (1) with acetone in the presence of aqueous K2CO3 afforded 3-C-acetonyl-1,2-O-isopropylidene-5-O-tertbutyl-dimethylsilyl-α-D-ribofuranose(2). Similar reaction of 1,2:5, 6-di-o-isopropylidene- α-D-ribo-hexofuranos-3-ulose (3) afforded 3-C-acetonyl-1,2:5, 6-di-o-isopropylidene- α-D-allofuranose (4) and (1R, 3R, 7R, 8S, 10R)-perhydro-8-hydroxy-5,5,10-trimethyl-2,4,6,11,14-pentaoxatetracyclo[8,3,1,01,8,03,7] tetradecane. The stereochemistry of the new chiral centers were determined by 1H NOE experiments.

N-(glucopyranosid-3-yl)-D-alanyl-L-alanyl-D-isoglutamine and related tripeptide analogues of muramyl dipeptide

Abstract Four analogues of the immuunoadjuvant Muramyl dipeptide in which the D -lactic acid have been replaced by D -alanine and L -alanine have been prepared. Condensation of methyl and benzyl 2-acetamido-3-amino-4,6- 0 -benzylidene-2,3-dideoxy-α- D -glucopyranosides 3 and 4 with ethyl D , L -2-bromopropionate afforded the corresponding methyl 3-[ D - and L -1(ethoxycarbonyl)ethyl ]amino]-gluco-pyranosides 5 and 9 and the corresponding benzyl glycosides 6 and 10 . The absolute configurations of 5 , 6 , 9 and 10 were unequivocally determined by condensation of 3 and 4 with ethyl L -2-bromopropionate. Hydrolysis of 6 and 10 with KOH/MeOH, gave the benzyl 3-[[ D - and L -1-(carboxy)ethyl ]amino]-gluco-pyranosides 8 and 12 , which by condensation with L -Ala- D -isoGln-OMe and L-Ala-D-Gln-OMe followed by hydrogenolysis afforded the desired N -(2-acetamido-2,3-dideoxy-D-glucopyranosid-3-yl) derivatives of D -Ala- L -Ala- D -isoGln-OMe, D -Ala- L -Ala- D -Gln-OMe, L -Ala- L -Ala- D -isoGln-OMe, and L -Ala- L -Ala- D -Gln-OMe,