In the presence of strong bases (NaH, DBU, KOH), ethyl 4-chloromethyl-6-methyl-2-oxo1,2,3,4-tetrahydropyrimidine-5-carboxylate and 4-mesyloxymethyl-6-methyl-5-tosyl-1,2,3,4tetrahydropyrimidin-2-one are transformed into novel tricyclic compounds, diethyl 9-methyl-5methylene-3,11-dioxo-2,3,4,5,6a,7,10,11-octahydro-1,6-methano[1,3]diazepino[1,7-e][1,3,5]triazocine-6,8(1H)-dicarboxylate and 9-methy...

New benzo[a]naphthacenequinone metabolites, designated bequinostatins A and B, have been isolated from the culture broth of the benastatin-producing strain Streptomyces sp. MI384-DF12. The structures of bequinostatins A and B were determined by spectral analyses to be 5,6,8,13-tetrahydro-1,6,7,9,11-pentahydroxy-8,13-dioxo-3- pentylbenzo[a]naphthacene-2-carboxylic acid and 2-decarboxybequinostat...

In the title compound, [Cu(CH(3)CO(2))(C(12)H(11)N(2)O(4))(H(2)O)](n), the Cu(II) cation is tetra-coordinated by three carboxyl-ate O atoms from one 4-[N'-(2,4-dioxo-3-pentyl-idene)-hydrazino]-benzoate ligand and two acetate bridges, and by one water mol-ecule. The acetate bridges link adjacent Cu(II) cations, forming a chain. The crystal structure involves O-H⋯O hydrogen bonds.

Two new spiranoid withanolides, (20R,22R,23R)-12β ,17β ,22-trihydroxy-1-oxo-12,23-cycloergosta-2,24-dien-26,23-olide (3) and (23R)-5α ,6β ,12β ,21-tetrahydroxy-1,22-dioxo-12,23-cycloergosta-2,17,24-trien-26,23-olide (4) were isolated from plants of Jaborosa odonelliana and Jaborosa runcinata, respectively. Compounds 3 and 4 were characterized by a combination of spectroscopic methods (1D and 2D...

In this paper we report the synthesis of new compounds based on the pyrazole and isoxazole framework fused to a cycloalkene unit, and bearing as a substituent the 1-piperidinyl group as new examples of potential antipsychotic molecules. The general synthesis involves the acylation of a chloro-substituted cyclic ketone with a 1-substituted piperidine-4-carboxylate derivative, followed by heteroc...

in this work, different ethyl 2,4-dioxo-4-arylbutanoate derivatives were prepared and evaluated for their src kinase inhibitory activity. for this purpose, the appropriate substituted acetophenone derivatives reacted with diethyl oxalate in the presence of sodium ethoxide in dried ethanol to give the corresponding products. all compounds showed moderate activities comparing with staurosporine a...

Phosphorus pentoxide used on alumina (P2O5/Al2O3) as an inexpensive, eco-friendly and non-toxic acid catalyst for the one-pot synthesis of 1,8-dioxo-octahydroxanthenes via multi-component reactions under solvent-free conditions. The present approach offers several advantages such as short reaction times, high yields, easy purification, recovery and reusability of the catalyst.

In this study, aluminosilicate MCM-41 has been found to be an efficient catalyst for reaction betweendifferent benzaldehyde derivatives and 5,5-dimethyl-1,3-cyclohexanedione to give open chain analogue of1,8-dioxo-octahydroxanthene in excellent yields. No evidence for the formation of cyclization products wasobserved. The catalyst can be used several times after recovery.

The chemical composition of a dichloromethane extract of the South American liverwort Porella recurva has been examined. Two new pinguisane-type norsesquiterpenoid natural products were isolated: 6,11-epoxy-15-nor-3,4-dioxo-5,10-pinguisadien-12-acetate and 6,11-epoxy-15-nor-4-oxo-5,10-pinguisadien-12-acetate. In addition two known pinguisane-type sesquiterpenes were also isolated: norpinguisone...