85026-59-1

A synthetic approach to 4a-carba-d-lyxofuranose derivatives starting from d-lyxose is described. The protected 4a-carba-β-d-lyxofuranose was employed as the key intermediate for the synthesis of 4a-carba-d-lyxofuranose derivatives including novel 1-amino-1-deoxy-4a-carba-d-lyxofuranoses. Synthesized 4a-carba-d-lyxofuranoses were evaluated as inhibitors of GH38 α-mannosidases, namely, the Golgi (GMIIb) and lysosomal (LManII) α-mannosidases from Drosophila melanogaster and commercial Jack bean α-mannosidase (JBMan) from Canavalia ensiformis. The biochemical evaluation revealed that only 1-amino-1-deoxy-4a-carba-β-d-lyxofuranose exhibited reasonable inhibitory activity against GMIIb (IC50 = 200 μm). In addition, the results of biological evaluation were discussed by means of molecular modelling.

The present invention provides for stable nicotinamide adenine dinucleotide (NAD/NADH) and nicotinamide adenine dinucleotide phosphate (NADP/NADPH) derivatives of formula (I), enzyme complexes of these derivatives and their use in biochemical detection methods and reagent kits.

Carba-NAD is a synthetic compound identical to NAD except for one substitution, where an oxygen atom adjacent to the anomeric linkage bearing nicotinamide is replaced with a methylene group. Because it is inert in nicotinamide displacement reactions, carba-NAD is an unreactive substrate analogue for NAD-consuming enzymes. SIRT3 and SIRT5 are NAD-consuming enzymes that are potential therapeutic targets for the treatment of metabolic diseases and cancers. We report an improved carba-NAD synthesis, including a pyrophosphate coupling method that proceeds in approximately 60% yield. We also disclose the X-ray crystal structures of the ternary complexes of SIRT3 and SIRT5 bound to a peptide substrate and carba-NAD. These X-ray crystal structures provide critical snapshots of the mechanism by which human sirtuins function as protein deacylation catalysts.

The present invention relates to a method for the synthesis of N-substituted carboxylated pyridinium compounds by reacting a pentamethine precursor with a primary amine. In this reaction an N-substituted alkoxycarbonyl pyridinium heterocycle is formed.

A chiral, divergent synthesis of two carbafuranosylamines, 1 and 2, two carbapyranosylamines, 3 and 4, two carbafuranosylamino acids, 5 and 6, and two carbapyranosylamino acids, 7 and 8, has been achieved. Highlights of the procedure include the following: a diastereoselective crossed vinylogous Mukaiyama aldol coupling between N-(tert-butoxycarbonyl)-2-[(tert-butyldimethylsilyl)-oxy]pyrrole (TBSOP, 9) and 2,3-O-isopropylidene-D-glyceraldehyde (10) for the assembly of the target compound carbon backbone; a high-yielding silylative cycloaldolization that gives the cyclopentanoid and cyclohexanoid motifs; and a reductive or hydrolytic breakage of the lactam C(O)-N link to liberate the carbasugar and install the desired pseudo-anomeric amine and the hydroxymethyl or carboxyl functionalities. The sequences leading to trans-configured carbafuranosyl compounds 1 and 5 and carbapyranosyl compounds 3 and 7 were 12- and 13-step processes, with overall yields of 34%, 35%, 17%, and 16%. Cis-configured isomers 2, 4, 6, and 8 were obtained only in minor yields.

The sequence-specific recognition of double-helical DNA by oligonucleotide-directed triple helix formation is limited primarily to purine tracts. To identify potential lead compounds which are able to extend the sequence repertoire of triple helical complexes, we designed two carbocyclic nucleosides with nucleobases attached via amide bonds. N 5-[(1R,2S,3R,4R)-3-hydroxy-4-(hydroxymethyl)-2-methoxycyclopentyl]-2- {[1H-pyrrol-2-yl)carbonyl]-amino}thiazole-5-carboxamide (L1) and 2-benzamido-N 5-[(1R,2S,3R,4R)-3-hydroxy-4-(hydroxymethyl)-2-methoxycyclopentyl] thiazole-5-carboxamide (L2) were synthesized and incorporated into pyrimidine oligonucleotides. The 2-(trimethylsilyl)ethoxymethyl (SEM) protecting group for the 1H-pyrrole NH was found to be compatible with DNA solid-phase synthesis of pyrimidine oligonucleotides. By quantitative DNase I footprinting analysis, both nonnatural nucleosides L1 and L2 showed preferential binding of pyrimidine over purine bases: L1/2 · (C-G) ≈ L1/2 · (T · A) > L1/2?(G · C) ≈ L1/2 · (A · T). Comparison with the previously reported nonnatural nucleosides with extended aromatic nucleobases 1-(2-deoxy-β-D-ribofuranosyl)-4-(3-benzamidophenyl)-imidazole (D3) and N4-[6-(benzamido)pyridin-2-y1]-2′-deoxycytidine (bzM) suggests that the observed binding selectivity C · G ≈ T · A > G · C ≈A · T for the nucleoside analogs L1, L2, D3, and bzM is derived from sequencespecific intercalation with preferential stacking of their nucleobases over pyrimidine · purine Watson-Crick base pairs.

An enantioselective synthesis of functionalized cyclopentanes has been used to access carbocyclic nucleoside analogs. This pathway allows access to carbocyclic C- or carbocyclic N-nucleosides from a common intermediate, ester 16. Additionally, (1R,2R,3S,4R)-4-amino-2,3-dihydroxy-1-cyclopentanemethanol (18), an intermediate in the total synthesis of aristeromycin, has been prepared as a single enantiomer in eight isolated steps from cyclopentadiene. Progress toward the synthesis of novel carbocyclic C-nucleosides is also discussed.

Enantiomerically pure (+)-as well as (-)-aristeromycin can be synthesized starting from (+)- or (-)-butyl (or hexyl) 4-acetamido-cyclopent-2-ene carboxylate; these carboxylates are easily obtained from their corresponding racemates by hydrolysis with the lipase from Candida rugosa.

Administration of doubly-labelled forms of D-glucose to the fermentation broth of Streptomyces citricolor followed by isotopic trapping has provided evidence for the intermediacy of a 2α,3α-dihydroxy-4β-(hydroxymethyl)cyclopentane-1β-amine 7 or 8 in the biosynthesis of the nucleoside antibiotic aristeromycin 1.

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Sodium borohydride reduction of (1S,3S,4S)-1--3,4-(isopropylidenedioxy)-2-cyclopentanone (11), which was prepared from D-erythrose, proceeds exlusively from the β-face to provide 2R-hydroxyl derivative 12.Compound 12 is a derivative of carbocyclic analogue of β-L-lyxofuranose.Silica gel promoted configurational inversion at the branched carbon in 11 followed by sodium borohydride reduction provides 1R,2R diastereomer 17 and 12 a 2.8:1 ratio.The former is a protected form of carboxylic α-D-ribofuranose.Replacement of the mesyloxy group in 23, which was derived from 17, by a hydroxyl group in a SN2 fashion and deprotection of the product followed by acetylation gave a derivative of carbocyclic α-D-xylofuranose 24.Compound 17 was also converted to compound 7, a key intermediate for the synthesis of the carboxylic nucleoside antibiotic (-)-aristeromycin (1), via a SN2 replacement of the mesyloxy group in 26 by an azide group.

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The title compound, an enantiomerically pure carbocyclic portion of the antibiotic (-)-aristeromycin, has been synthesized from D-erythrose.The synthesis involves a transformation of the known carbocyclic analogue of β-L-arabinofuranose to the α-D-ribo fo

A new, efficient synthetic route to (+/-)- and (-)-aristeromycin (1) has been developed which has as its key feature the cycloaddition of singlet oxygen to 5--1,3-cyclopentadiene (8) followed by in situ reduction to give ene diol 10.This reaction has been optimized and scaled-up to give 197 g (60percent) of partially purified 10.The key intermediate azide 15 was prepared from the partially purified 10 in 56percent yield by a three-step sequence of epoxidation to give 13, reaction with NaN3, and acetonation.Azide 15 was converted by standard chemistry via adenine intermediate 22 to (+/-)-aristeromycin (1) in 31percent overall yield.Intermediate 22 was also prepared in 25percent yield by a novel and shorter sequence which involved the reaction of epoxide 13 with the sodium salt of adenine and then acetonation.Alternatively, azide 15 was resolved by conversion to its naproxen ester 26, and the (-)-isomer of 15 was converted to the known amino triol 31, thus constituting a formal synthesis of (-)-aristeromycin.