Environmentally benign synthesis, molecular properties prediction and anti-inflammatory activity of novel isoxazolo[5,4-d]isoxazol-3-yl-aryl-methanones via vinylogous Henry nitroaldol adducts as synthons.

Synthesis of novel 6-methylisoxazolo[5,4-d]isoxazol-3-yl-aryl-methanones 5 has been achieved via nitro-nitrite rearrangement by utilizing vinylogous nitroaldol adducts as synthons under mild conditions. Furthermore, the new series of compounds 5a-i were assessed for molecular properties prediction, drug-likeness by Molinspiration (Molinspiration, 2008) & MolSoft (MolSoft, 2007) softwares, lipophilicity and solubility parameters using ALOGPS 2.1 program. The new series of compounds 5a-i were screened for their anti-inflammatory activity.

Bioactivity-guided isolation of cytotoxic constituents from stem-bark of Premna tomentosa.

A bioassay-guided fractionation and chemical investigation of the stem bark of Premna tomentosa resulted in the isolation and characterization of four new icetexane diterpenes (1-4), along with the known compounds coniferaldehyde (5), syringaldehyde (6), lupeol (7), betulin (8), and 2-(4-methoxyphenyl)-2-butanone (9). Their structures were established on the basis of extensive spectroscopic (IR, MS, 2D NMR) data analysis and by comparison with the spectroscopic data reported in the literature. The new compounds exhibited diverse functionalities on a common icetexane diterpene skeleton. In addition, cytotoxic activities of the icetexanes (1-3) were evaluated by determining their inhibitory effects on the human cancer cell lines (MCF-7, HT-29, Hep-G2, A-431, and A-549). Compounds 1 and 3 showed selective inhibitory activity against MCF-7 (15.96microg/mL and 15.84microg/mL) and HT-29 cell lines (16.21microg/mL and 14.57microg/mL), respectively.

Design, synthesis, antimicrobial, anti-inflammatory and analgesic activity of novel isoxazolyl pyrimido[4,5-b]quinolines and isoxazolyl chromeno[2,3-d]pyrimidin-4-ones.

Novel series of 2-methyl-3-{3-methyl-5-[(E)-2-phenyl-1-ethenyl]-4-isoxazolyl}-3,4-dihydropyrimido[4,5-b]quinolin-4-ones 5 and 3-{3-methyl-5-[(E)-2-phenyl-1-ethenyl]-4-isoxazolyl}-3,4-dihydro-2H-chromeno[2,3-d]pyrimidin-4-ones 7 have been synthesized from isoxazolyl cyanoacetamide synthon 2. Compound 2 was obtained by reaction of 4-amino-3-methyl-5-styrylisoxazole 1 with ethyl cyanoacetate. Isoxazolyl pyrimido[4,5-b]quinolin-4-ones 5 were obtained from compounds 2 by condensation with o-nitro benzaldehyde followed by treatment with SnCl(2) and subsequent tandem N-acetylation and cyclodehydration with acetic anhydride. Compounds 2 were converted to isoxazolyl chromeno[2,3-d]pyrimidin-4-ones 7 by reaction with salicylaldehydes and subsequent cyclization with formaldehyde. Compounds 2-7 were characterized by IR, (1)H NMR, (13)C NMR, and Mass spectral data. The title compounds 5a-f and 7a-g were evaluated for their antimicrobial, anti-inflammatory and analgesic activity. Compounds 5d and 7e exhibited significant antimicrobial activity, potent anti-inflammatory and analgesic activities as that of standard drugs.

Design, synthesis, in vitro antimicrobial and anticancer activity of novel methylenebis-isoxazolo[4,5-b]azepines derivatives.

A series of novel methylene bis-isoxazolo[4,5-b]azepines have been synthesized by reaction of 3,5-dimethyl-4-nitroisoxazole 6 with an appropriate methylene bis-chalcones 7 to obtain various Michael adducts 8a-i, which on treatment with SnCl(2)-MeOH underwent reductive cyclization to afford the title compounds 9a-i. Structure of these compounds were established on the basis of IR, (1)H NMR, (13)C NMR and mass spectral data. The title compounds 9a-i were evaluated for their in vitro antimicrobial and anticancer activities. Compounds 9h and 9i exhibited potent antimicrobial and anticancer activities as that of standard drugs.