Synthesis and Antiinflammatoryand Anticancer Activity Evaluation of Some Condensed Pyrimidines

Summary.  Upon condensation with 4-isothiocyanato-4-methyl-2-pentanone, 2,3-diaminonaphthalene and N-aminoethyladenosine gave in good yields substituted pyrimidonaphthoimidazole and imidazopyrimidine thione. Refluxing pyrimidobenzthiazole with methanol H₂SO₄ at pH∼1 resulted in S-methyl pyrimidobenzthiazole in moderate yield. Pyrimidobenzimidazole derivatives could be reacted to S-alkylated and N-acylated derivatives by refluxing with ethyl bromoacetate in the presence of anhydrous potassium carbonate in THF and by heating in an acetic acid/acetic anhydride mixture. Heating of pyrimidobenzimidazole with 75% aqueous H₂SO₄ on a water bath ended up in a rearranged product. All compounds gave correct ¹H NMR, IR, and HR mass spectra. Results of antiinflammatory, analgesic, and anticancer activity screening of the new compounds are described. Received October 29, 1999. Accepted (revised) January 13, 2000     

On Wachspress pentagonal patches

Wachspress quadrilateral patches have been recently studied from the point of view of applications to surface modelling in CAGD [1], [3], [4]. Some more applications for defining barycentric coordinates for arbitrary polygons have also been presented in [5] [9]. The purpose of the present paper is to introduce non-negative Wachspress rational basis functions for surface modelling on pentagonal partitions. Interpolation formula for function values and directional derivatives at the vertices of pentagon has been presented. Conditions for C¹– continuity of the composite surface have also been studied in the paper. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)     

Minimizing flow time in cyclic schedules for identical jobs with acyclic precedence: the bottleneck lower bound

This paper studies minimizing the flow time of a cyclic schedule for repeated identical jobs, where one job is started/completed in each cycle, subject to the schedule achieving maximum throughput. We propose a branch and bound method for a single machine problem, and use this method to derive an improved lower bound for the multiple machine problem.     

Antibacterial activity of a triterpenoid saponin from the stems of Caesalpinia pulcherrima Linn.

A new compound 1 was isolated from the methanolic extract of the stems of the Caesalpinia pulcherrima Linn. along with a reported compound (2) 3-O-β-D-glucopyranosyl-(1→4)-β-D-xylopyranosyl-(1→3)-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl hederagenin 28-O-β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl ester. The new compound 1 has m.p. 272–274°C, m.f. C₄₆H₇₄O₁₇, [M]⁺ m/z 898. It was characterised as 3-O-β-D-glucopyranosyl-(1→4)-α-L-arabinopyranosyl hederagenin 28-O-β-D- xylopyranosyl ester by various colour reactions, chemical degradations and spectral analyses. Antibacterial activity of compound 1 was screened against various Gram-positive and Gram-negative bacteria and showed significant results.     

The regiospecific synthesis of N-substituted pyrazoles. I. 1- and 2-substituted indeno[1,2-c]pyrazol-4(1H)-ones

The reaction of the enaminoketones ( 2 or 5 ) of 2-acyl-1,3-indandiones with unsymmetrical hydrazines results in the regiospecific synthesis of 1,3- or 2,3-disubstituted indeno[1,2-c]pyrazol-4(1H)-ones ( 4 or 7 ). The synthesis of the enaminoketones ( 2 or 5 ) is accomplished by way of amine addition to the 2-acyl-1,3-indandiones 8a-c or by reduction of the indenoisoxazole 9 . The structural assignment of the isomeric indenopyrazoles 4 and 7 is based upon ¹H-nmr chemical shifts.     

Biologically Relevant Macrocyclic Complexes of Copper Spectral, Magnetic, Thermal and Antibacterial Approach

Copper(II) macrocyclic complexes have been synthesized with five novel ligands: L¹-1,7,10,16-tetraaza-2,6,11,15-tetraone-4,13-dithiacycloocta-decane, L²-1,7,11,17-tetraaza-2,6,12,16-tetraone-4,14-dithia-cyclocosane, L³-1,7,10, 13,19,22-hexaaza-2,6,14,18-tetraone-4,16-dithiacyclo-tetracosane, L⁴-1,7,14,20,tetraaza-2,6,15,19-tetraone-4,17,di- thiatricyclo [22, 4, O^21,26, O^8,13] hexacosa-8,10,12,21,23,25-hexene, L⁵- 1,7,13,19,25,26-hexaaza-2,6,14,18 tetraone-4,16 dithia tricyclo [23, 3, 1, I^8,12] hexacosa [8(26), 10, 12, 20(25), 22, 24] hexane and characterized by elemental analysis, molar conductance, magnetic susceptibility, i.r, u.v.–vis, EPR spectral studies, thermal studies and electrochemical properties. The molar conductance measurements of the complexes in DMSO correspond to 1:2 electrolytes. g-Values are calculated for all of the complexes in the polycrystalline form as well as in DMSO solution. On the basis of i.r, electronic and EPR spectral studies a square planar geometry has been assigned to these complexes. Cyclic voltammograms for all the complexes are similar to quasi-reversible redox processes Cu^IICu^II⇆Cu^IICu^I⇆Cu^ICu^I. The complexes were also evaluated against the growth of bacteria (S. fecalis and E.coli) in vitro. An erratum to this article is available at .     

Kinetics of the non-isothermal decomposition of some metal hippurates from DTG curves

Calculated vapor pressures have been used to estimate the composition of the vapor over an equimolar mixture of linear alkanes and to make inferences about the effects of pressure on the thermal degradation of polyethylene as studied using thermogravimetry. The troublesome bubbling in molten PE degrading under vacuum conditions has been related to the boiling out of molecules in the range C₃₀ to >C₈₀. The effect of pressure in lowering the apparent overall activation energy has been ascribed to contributions from the lalent heats of vaporization of molecules in the range C₁₅ to ～C₃₀.     

Facile conversion of lactols to lactones using IBX

Lactols, which are insoluble or only sparingly soluble in most of the organic solvents that are generally employed for oxidation, are converted to lactones using o-iodoxybenzoic acid (IBX) in a facile manner under modified experimental conditions [EtOAc-DMSO (9:1) mixture at reflux] in good to excellent isolated yields (66-91%).