A series of methyl 2-(2-(2-arylquinazolin-4-yl)oxy) acetylamino alkanoate have been developed via N,N 0dicyclohexylcarbodiimide coupling of (2-arylquinazolin-4-yloxy) acetic acids with amino acid ester hydrochlorides. The O-substituted carboxylic acids were prepared by two-step reactions from the corresponding 2arylquinazolin-4(3H)-one starting with chemoselective O-alkylation with ethyl chloroacetate and then hydrolysis of the produced esters. The reason for this O-chemoselective behavior of 2-arylquinazolin-4(3H)one toward electrophiles was explained by theoretical density functional theory computational calculations on the model compound 2-phenylquinazolin-4(3H)-one. The antimicrobial activity of the synthesized compounds was evaluated, showing the best inhibition zone for (2-arylquinazolin-4-yloxy) acetic acids, methyl 2-(2-(2-arylquinazolin-4-yl)oxy) acetylamino acetates, and methyl 2-(2-(2-phenylquinazolin-4-yl)oxy) acetylamino-3-methylbutanoate.Scheme 2. Synthesis of methyl 2-(2-(2-arylquinazolin-4-yl)oxy) acetylamino alkanoates 7-8(a-f).

A series of methyl 2-(2-(2-arylquinazolin-4-yl)sulfanyl)acetylamino alkanoates have been developed on the basis of the S-chemoselective reaction of 2-arylquinazolin-4(3H)-thione with ethyl chloroacetate and N,N 0 -dicyclohexylcarbodiimide coupling method with amino acid ester hydrochloride. The precursor 2arylquinazolin-4(3H)-thione was prepared by a new thiation method from 2-arylquinazolin-4(3H)-one by a two-step reaction that includes chlorination and then the reaction with N-cyclohexyldithiocarbamate cyclohexyl ammonium salt. The antimicrobial activity of the synthesized compounds was tested in vitro via paper-disc agar-plate method against two bacterial strains Gram-positive bacteria Staphylococcus aureus and Gram-negative bacteria Escherichia coli and a pathogenic yeast Candida albicans. Most synthesized compounds showed remarkable antibacterial activity against E. coli overpassing the standard reference antibiotics applied: tetracycline, erythromycin, and novobiocin. On the other hand, most synthesized compounds gave moderate antifungal activity against pathogenic yeast C. albicans. Scheme 1. Synthesis of 2-((2-arylquinazolin-4-yl)thio)acetic acid 6a-b.

The influence of the nuclear polyhedrosis virus of Heliothis armigera (Hübner) (HANPV) on the various developmental stages was investigated. The effect of temperature was also studied. Results indicated that the first instar larvae of H. armigera were more susceptible to HANPV than the second instar and the mortality of the larvae increased with the increase of viral concentration. The median lethal doses (LD50) were 16 × 106 and 25 × 106 PIB/ml for the first and second instar, respectively. The larvae that survived after NPV‐treatment showed an obvious reduction in pupation and emergence percentage. Investigations on the effect of temperature indicated that the increase of temperature caused an increase in the larval mortality after exposure to HANPV. When the moths of H. armigera were fed on a diet contaminated with HANPV, the effect on egg production and fertility was more pronounced than if the treatment was applied during the larval instars. Zusammenfassung Zur Wirkung des HANPV‐Virus auf die Baumwolleule, Heliothis armigera Hbn. Es wurde der Einfluß der Kernpolyedrose von H. armigera auf deren Entwicklungsstadien untersucht. Dabei wurde auch die Wirkung der Temperatur berücksichtigt. Aus den Ergebnissen geht hervor, daß die L1 von H. armigera das gegen HANPV empfindlichste Stadium waren, gefolgt von den L2. Die Mortalität der Raupen stieg mit der Zunahme der Virus‐Konzentration. Die mittlere letale Dosis (LD50) betrug 16 × 106 bzw. 25 × 106 PIB/ml für L1 bzw. L2. Raupen, die eine Behandlung mit der Virose überstanden, zeigten eine deutliche Verringerung der Verpuppungs‐ und der Schlüpfquote. Untersuchungen über den Temperatur‐Einfluß zeigten, daß zunehmende Temperatur mit zunehmender Mortalität der mit HANPV infizierten Raupen verbunden war. Wenn die Falter von H. armigera mit einer HANPV‐haltigen Diät gefüttert wurden, war die Wirkung auf die Eiproduktion und die Fertilität deutlicher als nach entsprechender Fütterung der Raupen.

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http://eajbsa.journals.ekb.eg/ The Effect of Planting Dates and Nitrogen Fertilizer on Aphis craccivora (koch) Infestation in Faba Bean (Vicia faba, L.