1. 5-Benzamidoisoquinolin-1-ones and 5-(ω-carboxyalkyl)isoquinolin-1-ones as isoform-selective inhibitors of poly(ADP-ribose) polymerase 2 (PARP-2)
Peter T Sunderland, et al. J Med Chem. 2011 Apr 14;54(7):2049-59. doi: 10.1021/jm1010918. Epub 2011 Mar 18.
PARP-2 is a member of the poly(ADP-ribose) polymerase family, with some activities similar to those of PARP-1 but with other distinct roles. Two series of isoquinolin-1-ones were designed, synthesized, and evaluated as selective inhibitors of PARP-2, using the structures of the catalytic sites of the isoforms. A new efficient synthesis of 5-aminoisoquinolin-1-one was developed, and acylation with acyl chlorides gave 5-acylaminoisoquinolin-1-ones. By examination of isoquinolin-1-ones with carboxylates tethered to the 5-position, Heck coupling of 5-iodoisoquinolin-1-one furnished the 5-CH═CHCO(2)H compound for reduction to the 5-propanoic acid. Alkylation of 5-aminoisoquinolin-1-one under mildly basic conditions, followed by hydrolysis, gave 5-(carboxymethylamino)isoquinolin-1-one, whereas it was alkylated at 2-N with methyl propenoate and strong base. Compounds were assayed in vitro for inhibition of PARP-1 and PARP-2, using FlashPlate and solution-phase assays, respectively. The 5-benzamidoisoquinolin-1-ones were more selective for inhibition of PARP-2, whereas the 5-(ω-carboxyalkyl)isoquinolin-1-ones were less so. 5-Benzamidoisoquinolin-1-one is the most PARP-2-selective compound (IC(50(PARP-1))/IC(50(PARP-2)) = 9.3) to date, in a comparative study.
2. Synthesis and preliminary evaluation of some N-[5-(2-furanyl)-2-methyl-4-oxo-4H-thieno[2,3-d]pyrimidin-3-yl]-carboxamide and 3-substituted-5-(2-furanyl)-2-methyl-3H-thieno[2,3-d]pyrimidin-4-ones as antimicrobial agents
Ravindra V Chambhare, Barsu G Khadse, Anil S Bobde, Rajesh H Bahekar Eur J Med Chem. 2003 Jan;38(1):89-100. doi: 10.1016/s0223-5234(02)01442-3.
Two series of N-[5-(2-furanyl)-2-methyl-4-oxo-4H-thieno[2,3-d]pyrimidin-3-yl]-carboxamide (4a-m) and 3-substituted-5-(2-furanyl)-2-methyl-3H-thieno[2,3-d]pyrimidin-4-ones (5a-m) were synthesised using appropriate synthetic route. All the test compounds 4a-m and 5a-m were assayed in vitro for antibacterial activity against two different strains of Gram-negative (Escherichia coli and S. typhi) and Gram-positive (S. aureus, B. subtilis) bacteria and the antimycobacterial activity was evaluated against M. tuberculosis and M. avium strains. The minimum inhibitory concentration (MIC) was determined for test compounds as well as for reference standards. The test compounds have shown significant antibacterial and antimycobacterial activity against all the microbial strains used, when tested in vitro. In general, along with the thienopyrimidinone ring, substituted amido or imino side chain at position 3 is essential for antimicrobial activity. Among the compounds tested, compounds 4c, 4e and 4g in N-[5-(2-furanyl)-2-methyl-4-oxo-4H-thieno[2,3-d]pyrimidin-3-yl]-carboxamide series and compounds 5c, 5e and 5g in 3-substituted-5-(2-furanyl)-2-methyl-3H-thieno[2,3-d]pyrimidin-4-ones series were found to be the most potent. Further the toxicity of most potent compounds 4c, 4e and 4g and 5c, 5e and 5g were assessed using hemolytic assay and minimal hemolytic concentration (MHCs) were determined. In general, test compounds were found to be non-toxic up to a dose level of 200 micromol L(-1) (MHC).
3. Synthesis of 3-substituted benzamides and 5-substituted isoquinolin-1(2H)-ones and preliminary evaluation as inhibitors of poly(ADP-ribose)polymerase (PARP)
C Y Watson, W J Whish, M D Threadgill Bioorg Med Chem. 1998 Jun;6(6):721-34. doi: 10.1016/s0968-0896(98)00029-7.
Inhibitors of poly(ADP-ribose)polymerase (PARP) inhibit repair of damaged DNA and thus potentiate radiotherapy and chemotherapy of cancer. 3-Substituted benzamides and 5-substituted isoquinolin-1-ones have been synthesised and evaluated for inhibition of PARP. Reduction of 3-(bromoacetyl)benzamide, followed by treatment with base, gave RS-3-oxiranylbenzamide. Reduction of 3-(hydroxyacetyl)benzonitrile with bakers' yeast gave the R-diol which was converted to R-3-(1,2-dihydroxyethyl)benzamide. Similar reduction of 3-(acetoxyacetyl)benzonitrile led towards the S-diol which was converted to its cyclic acetonide. E-2-(2,6-Dicyanophenyl)-N,N-dimethylethenamine was formed by condensation of 2,6-dicyanotoluene with dimethylformamide dimethyl acetal (DMFDMA); cyclisation under acidic conditions afforded 5-cyanoisoquinolin-1-one. Heck coupling of 5-iodoisoquinolin-1-one with propenoic acid formed E-3-(1-oxoisoquinolin-5-yl)propenoic acid. 3-Oxiranylbenzamide, 5-bromoisoquinolin-1-one and 5-iodoisoquinolin-1-one were among the most potent inhibitors of PARP activity in a preliminary screen in vitro.
