N-ribosylation and N-mannosylation compounds have a great role in compounds activity as anticancer. The reaction of 2-thioxo-4-thiazolidinone (rhodanine) derivatives, as aglycon part, was done with ribofuranose and mannopyranose sugars (glycone part) followed by deacetylation without cleavage of the rhodanine under acidic medium. Conformational analysis has been studied using NMR methods (2D, DQF-COSY, HMQC and HMBC).
View Article and Find Full Text PDFN- and S-galactosylation was carried out via the reaction of 5-((Z)-arylidene)-2-thioxo-4-thiazolidinones with 2,3,4,6-tetra-O-acetyl-α-d-galactopyranosyl bromide under alkaline conditions or under silylation conditions. Deacetylation of the N-galactosylation products was performed with concentrated hydrochloric acid in methanol (3.5%) or sodium methoxide in methanol without cleavage of the 2-thioxo-4-thaizolidinone ring by means of acid hydrolysis.
View Article and Find Full Text PDFNew benzofuranones were synthesized and evaluated toward NCI-H661 non-small cell lung cancer cells. Benzamide derivatives possessed micromolar antiproliferative and histone deacetylase inhibitory activities and modulate histone H4 acetylation. Hydroxamic acids were found to be potent nanomolar antiproliferative agents and HDAC inhibitors.
View Article and Find Full Text PDFTwo glucuronide prodrugs of the histone deacetylase inhibitor CI-994 were synthesized. These compounds were found to be soluble in aqueous media and stable under physiological conditions. The carbamoyl derivatisation of CI-994 significantly decreased its toxicity towards NCI-H661 lung cancer cells.
View Article and Find Full Text PDFA variety of alkynylated amines, amides, and imides are reacted in the superacid system HF-SbF5 to give regioselectively new beta-gem-difluoroamines. The reaction, which is not observed in pure HF, is consistent with the formation of a dicationic intermediate (i.e.
View Article and Find Full Text PDFNew compounds derived from inhibitors of histone deacetylases (HDACs) have been synthesized and their antiproliferative activities towards non small lung cancer cell line H661 evaluated. Their design is based on hybrids between indanones to limit conformational mobility and other known HDAC inhibitors (SAHA, MS-275). The synthesis of these new derivatives was achieved by alkylation of appropriate indanones to introduce the side chain bearing a terminal ester group, the latter being a precursor of hydroxamic acid and aminobenzamide derivatives.
View Article and Find Full Text PDFNew histone deacetylase inhibitors have been synthesized and evaluated for their activity against non-small lung cancer cell line H661. These compounds have been designed with diversely substituted 1,4-benzodiazepine-2,5-dione moieties as cyclic peptide mimic cap structures, and a hydroxamate side chain. Biological evaluations demonstrated that benzodiazepine-based HDACi bearing an aromatic substituent at the N1 position exhibited promising antiproliferative and HDAC-inhibitory activities.
View Article and Find Full Text PDFThe first O-glycosylation of hydroxamic acids is reported. This process involves the use of glycosyl N-phenyl trifluoroacetimidates as glycosyl donors in the presence TMSOTf and 4 A molecular sieves in dichloromethane. Under such conditions, a wide range of new glycosyl donors including glucosyl, galactosyl, mannosyl, glucuronyl, and ribosyl hydroxamates were prepared in good to high yields.
View Article and Find Full Text PDFClick chemistry has became an important tool for molecular constructs such as biopolymers. During the development of biodegradable multifunctional poly(ethylene oxide) (PEO) polymers suitable for click chemistry in water, an unexpected reaction leading to a mixture of triazole cycloadducts was observed. This result was attributed to an intramolecular ligand effect, and alternative conditions were evaluated.
View Article and Find Full Text PDFThe beta-O-glucuronide and beta-O-galactoside of SAHA have been prepared and evaluated as prodrugs for selective cancer chemotherapy (ADEPT, PMT). These new compounds are stable under physiological conditions and do not exhibit any antiproliferative activity compared to the parent drug after a 48-h treatment of H661 cells. The glucuronide derivative did not lead to the release of the drug in the presence of either Escherichia coli or bovine liver beta-glucuronidase.
View Article and Find Full Text PDFNew inhibitors of histone deacetylase (HDAC) have been synthesized and evaluated for their activity toward non small lung cancer cell line H661. Their design is based on indanone (or tetralone) systems leading to trichostatin A (TSA) analogs with limited conformational mobility. Molecular modelization at the AM1 level revealed that the conformations of indane-based analogs and TSA bound to HDAC like protein are similar.
View Article and Find Full Text PDFThe synthesis, enzymatic hydrolysis and self decomposition of model glucuronylated prodrugs, incorporating a new linker with different aryl substituents, have been studied. Determination of kinetic parameters (V(max), K(m) and t(1/2)) showed the important role of aromatic substitution in enzymatic recognition and linker decomposition.
View Article and Find Full Text PDFNucleosides Nucleotides Nucleic Acids
November 2003
A modified nitrogen and sulfur glycosylation reaction involving benzothiazole benzoxazole and pyridine nucleoside bases with furanose and pyranose sugars are described. Conformational analysis has been studied by homo- and heteronuclear two-dimensional NMR methods (2D DFQ-COSY, HMQC and HMBC). The N and S sites of glycosylation were determined from the 1H, 13C heteronuclear multiple-quantum coherence (HMQC) experiments.
View Article and Find Full Text PDF[reaction: see text]. (-)-PF1163B, a new macrocyclic antifungal antibiotic isolated from Streptomyces sp., has been prepared in eight steps from (S)-citronellene.
View Article and Find Full Text PDFRegiospecific synthesis of title compounds is based either on cycloaddition of ketene acetals derived from Hagemann's ester or of homophthalic anhydrides. Thus, tetracenomycin D and 3,8-di-O-methyl saintopin have been prepared in few steps. New derivatives of 10-deoxysaintopin have been also obtained.
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