13316-98-8Relevant articles and documents
Substituent effects on energetics of peptide-carboxylate hydrogen bonds as studied by 1H NMR spectroscopy: Implications for enzyme catalysis
Emenike, Bright U.,Liu, Albert Tianxiang,Naveo, Elsy P.,Roberts, John D.
, p. 11765 - 11771 (2013)
Substituent effects in N-H···O hydrogen bonds were estimated by comparing the acidities of two series of model compounds: N-benzoylanthranilic acids (A) and 4-benzoylamidobenzoic acids (B). Intramolecular N-H···O hydrogen bonds were found to be present in the A series of compounds, while B acids were used as control models. The respective pKa values for A and B acids were determined experimentally in DMSO solution using proton NMR spectroscopy. With X = H, the pKa for A and B acids were observed to be 7.6 and 11.6, respectively, a difference of 4.0 units (ΔpKa). However, with X = p-NO 2, the ΔpKa value between A and B acids increased to 4.7 units: the pKa values for A and B acids were determined as 6.7 and 11.4, respectively. The ΔpKa values between A and B acids as a function of the X substituents were studied in 10 other examples. The effects of X substituents in A acids could be predicted on the basis of the observed linear Hammett correlations, and the sensitivity of each substituent effect was found to be comparable to those observed for the ionization of substituted benzoic acids (ρ = 1.04 for A acids, and ρ = 1.00 for benzoic acids).
Palladium catalyzed chemo- and site-selective C-H acetoxylation and hydroxylation of oxobenzoxazine derivatives
Bakthadoss, Manickam,Vijay Kumar, Polu,Kumar, Ravan,Agarwal, Vishal
supporting information, p. 4465 - 4469 (2019/05/16)
An efficient protocol for the introduction of acetoxy and hydroxy functionalities on unactivated aryl sp2 carbons of oxobenzoxazine derivatives via an ortho-C-H activation reaction using a palladium catalyst has been developed for the first tim
Novel synthesis of dianthalexin (Phytoalexin) analogues preparation
Hauteville,Ponchet,Ricci,Favre-Bonvin
, p. 715 - 718 (2007/10/02)
Two phytoalexins, previously isolated from carnation infected by Phytophthora parasitica D., were synthesized: 2-phenyl-7-hydroxy-4H-3,l-benzoxazin-4-one (Dianthalexin) and 2-(2-hydroxybenzoyl)-amino-4-methoxybenzoic acid (Dianthramide A). The first one w