Synthesis and biological evaluation of 2-, 3-, and 4-acylaminocinnamyl-N-hydroxyamides as novel synthetic HDAC inhibitors.
A new series of 2-, 3-, and 4-acylaminocinnamyl-N-hydroxyamides 1-3 have been prepared, and their anti-HDAC (against maize HD2, HD1-B, and HD1-A enzymes) activities have been assessed. Cinnamyl-hydroxyamides bearing acylamino substituents at the C2 position of the benzene ring (compounds 1a-g) showed very low HDAC inhibiting activities, with IC(50) values in the high micromolar range. By shifting the same acylamino groups from C2 to C3 (compounds 2a-g) as well as C4 (compounds 3a-f) position of the benzene ring, a number of highly potent HDAC inhibitors have been obtained. In the anti-HD2 assay 3c (IC(50) = 11 nM) was the most potent compound, being >11600-, 4.5-, and 10-fold more potent than sodium valproate, SAHA, and HC-toxin, respectively, and showing the same activity as trapoxin. HD1-B and HD1-A assays have been performed to screen the inhibitory action of 1-3 against mammalian class I (HD1-B) and class II (HD1-A) HDAC homologous enzymes. From the corresponding IC(50) data, a selectivity ratio has been calculated. In general, compounds 1-3 showed no or little selectivity towards the class II homologue HD1-A, the most selective being 2a with class II selectivity ratio = 4.3. About the inhibitory potency, the 4-(2-naphthoylamino)cinnamyl-N-hydroxyamide 3f showed the highest inhibiting effect against the two enzymes (IC(50-HD1-B) = 36 nM; IC(50-HD1-A) = 42 nM). Selected 2 and 3 compounds will be evaluated to determine their antiproliferative and cyto differentiating activities on HL-60 cells.
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Dipartimento di Studi Farmaceutici, Istituto Pasteur, Fondazione Cenci-Bolognetti, Università degli Studi di Roma La Sapienza, P. le A. Moro 5, 00185 Roma, Italy. antonello.mai@uniroma1.it
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Pezzi
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Loidl
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Brosch
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D000577:Amides / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology*; D004791:Enzyme Inhibitors / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology*; D006367:HeLa Cells; D056572:Histone Deacetylase Inhibitors; D006655:Histone Deacetylases / Q000737:chemistry; D006801:Humans; D008968:Molecular Conformation; D011487:Protein Conformation
D000577:Amides; D004791:Enzyme Inhibitors; D056572:Histone Deacetylase Inhibitors; D006655:Histone Deacetylases