17293-40-2Relevant articles and documents
PIII/PV=O Catalyzed Cascade Synthesis of N-Functionalized Azaheterocycles
Li, Gen,Luzung, Michael R.,Nykaza, Trevor V.,Radosevich, Alexander T.,Yang, Junyu
, p. 4505 - 4510 (2020)
An organocatalytic method for the modular synthesis of diverse N-aryl and N-alkyl azaheterocycles (indoles, oxindoles, benzimidazoles, and quinoxalinediones) is reported. The method employs a small-ring organophosphorus-based catalyst (1,2,2,3,4,4-hexamethylphosphetane P-oxide) and a hydrosilane reductant to drive the conversion of ortho-functionalized nitroarenes into azaheterocycles through sequential intermolecular reductive C?N cross coupling with boronic acids, followed by intramolecular cyclization. This method enables the rapid construction of azaheterocycles from readily available building blocks, including a regiospecific approach to N-substituted benzimidazoles and quinoxalinediones.
Chemical hybridizing agents for chickpea (Cicer arietinum L.): Leads from QSAR analysis of ethyl oxanilates and pyridones
Chakraborty, Kajal,Devakumar
, p. 1868 - 1873 (2007/10/03)
In the self-pollinated crops such as chickpea, induction of male sterility by deployment of chemical hybridizing agents (CHAs) facilitating "two-line" approach holds immense potential in heterosis breeding. A total of 40 test CHAs comprising 20 ethyl oxanilates and 20 pyridones were screened as potential CHAs on chickpea (variety BG 1088) at 500, 800, and 1000 ppm. Three test compounds mostly having either F (4)/Br (5)/CF3 (19) at the para position of the aryl ring from a pool of 20 ethyl oxanilates were identified as the most potent CHAs causing >99% induction of pollen sterility and >90% total flower sterility at 1000-ppm test concentration. Among pyridone derivatives, N-(4-chlorophenyl)-5-carbethoxy-4,6-dimethyl, 1,2-dihydropyrid-2-one (26) was found to be the most active. Quantitative structure activity relationship (QSAR) analysis has revealed a direct involvement of Swain-Lupton field constant, Fp, with the target bioactivity which implied that field rather than resonance effect (R) had a positive effect on the activity. The real guiding principle for selectivity was found out to be the hydrophobic parameter π value. The QSAR models indicated that increased steric bulk at the 4-position on the phenyl ring is associated with enhanced activity. The CHAs appeared to act by mimicking UDP-glucose, the key substrate in the synthesis of callose, or lead to an imbalance in acid-base equilibrium in pollen mother cells resulting in dissolution of callose wall by premature callase secretion.
Synthesis and quantitative structure-activity relationships of oxanilates as chemical hybridizing agents for wheat (Triticum aestivum L.)
Chakraborty, Kajal,Devakumar, Chakravarthi,Tomar, Shiv M. S.,Kumar, Rajendra
, p. 992 - 998 (2007/10/03)
Chemical hybridizing agents (CHAs) can facilitate two-line breeding in heterosis programs of crops. Twenty-seven oxanilates having different aromatic substitutions were synthesized and screened as CHAs on two genotypes of wheat, PBW 343 and HD 2733, during two Rabi (winter) seasons, 2000-01 and 2001-02. The oxanilates prepared by thermal condensation of anilines with diethyl oxalate or by acylation with ethoxycarbonyl methanoyl chloride were sprayed at 1000 and 1500 ppm at the premeiotic stage of wheat, when the length of the emerging spike of the first node was 7-8 mm. Pollen sterility and spikelet sterility were measured in each treatment. Ethyl oxanilates 5, 6, and 25, containing 4-F, 4-Br, and 4-CF3 aromatic substituents, respectively, induced greater than 98% spikelet sterility, the desired level, at 1500 ppm. Quantitative structure-activity relationship analysis revealed a direct relationship between Fp and molecular mass but an inverse relationship between MR, Es, and R in influencing the bioactivity. Several F1 hybrids were developed using 5, and at least one showed heterosis.
