RESUMO
To mitigate potentially severe food shortages due to the exponential growth of the global population, it is of paramount importance to improve the yield and quality of globally harvested food crops. As pest control contributes to both these aspects, the development of safe and effective pesticides is one of the main strategies pursued in this direction in the context of agricultural chemistry. During our investigation of natural pesticides, a supercritical CO2 fluid extract of Alcea nudiflora L. was found to exert extremely potent insecticidal activity against aphids (Macrosiphum euphorbiae) and cowpea seed beetles (Callosobruchus maculatus) with LC50 values of 0.03 mg/mL (24 h exposure, contact method). The facts that their insecticidal activity is in the most potent class among the essential oils known to date, and that the extract did not show any toxicity toward beneficial insects such as ladybugs (Coccinella magnifica) and European honeybees (Apis mellifera Linnaeus), indicate that this extract could be a good, natural, and safe new pesticide candidate. A compositional analysis of this extract was carried out using GC/MS.
RESUMO
Selective C-formyl-ation of 8,9,10,11-tetra-hydro-pyrido[2',3':4,5]pyrimido[1,2-a]-azepin-5(7H)-one has been studied for the first time. It was revealed that formyl-ation proceeds by the formation of an inter-mediate salt, which due to the re-amination process on treatment with aqueous ammonia transformed into the corresponding (E)-11-(amino-methyl-ene)-8,9,10,11-tetra-hydro-pyrido[2',3':4,5]-pyrimido[1,2-a]azepin-5(7H)-one, C13H14N4O, as an E-isomer. Formyl-ation was carried out by Vilsmeier-Haack reagent and the structure of the synthesized compound was confirmed by X-ray structural analysis, spectroscopic and LC-MS methods. In the mol-ecule, the seven-membered penta-methyl-ene ring adopts a twist-boat conformation.
RESUMO
The title compound, C17H12N4O3, a pyrido-pyrrolo-pyrimidine derivative, is almost planar. The nitro-benzene ring is inclined to the mean plane of the 8,9-di-hydro-pyrido[2,3-d]pyrrolo-[1,2-a]pyrimidin-5(7H)-one moiety (r.m.s. deviation = 0.023â Å) by 6.8â (1)°. In the crystal, mol-ecules are linked via C-Hâ¯O and C-Hâ¯N hydrogen bonds, forming layers parallel to (101).