p-Hydroxybenzoic acid (p-HOBA) was selected as the building block for s elf-assembly with five bas es, i.e., diethy lamine, tert-butylamine, cy clohexylamine, i midazole and pi perazine, and generation of t he correspon ding acid–base c omplexes 1–5. Cry stal structure analy ses suggest that proton -transfer from the carboxyl hydrogen to the nitrogen atom of the b ases can be observed in 1–4, w...

2D-TLC and RP-HPLC methods were applied to qualitatively determinate free phenolic acids and those liberated by acid and alkaline hydrolysis in the flowers and leaves of G. robusta and G. squarrosa. The presence of eleven phenolic acids, namely: caffeic, chlorogenic, p-coumaric, p-hydroxybenzoic, ferulic, gallic, protocatechuic, vanillic salicylic, p-hydroxyphenylacetic and ellagic acids was de...

Analysis by GC-MS/MS showed that a worldwide collection of 58 wheat accessions differed significantly in the amounts of 7 known phenolic acids exuded by the living roots of 17-day-old wheat seedlings. The quantities of exuded allelochemicals varied with the specific compound and ranged from 2.3 to 18.6, from 0.6 to 17.5, from 0.1 to 4.9, from 0.0 to 52.7, from 0.33 to 12.7, from 1.5 to 20.5, an...

Free radical copolymerization and cross-linking copolymerization of the 4-chloromethyl styrene (CMS) with styrene (in various mole ratios), were carried out using α,α-azobis(isobutyronitrile) AIBN as initiator and 1,4divinylbenzene (DVB) as a crosslinking agent at 70 oC. The antimicrobial 4-hydroxybenzoic acid (4-HBA) was covalently attached to the obtained copolymers with replacement of all th...

New biodegradable network polymers containing siloxane-linked polymeric prodrugs of 5-ammino-2-hydroxybenzoic acid (5-ASA) in the main chain were prepared by ter polymerization of methacrylic acid (MA), 2-hydroxyethylmethacrylate (HEMA), and bis (trimethylsilyloxy) methylsilane (VBM) in the presence of some new cross-linking agents.The monomers and polymers were characterized by FT-IR and 1H-NM...

Phenolic acids existed in many agricultural products especially vegetables and considered as important natural antioxidants. Eleven phenolic commonly were chosen to assess the antioxidant activities using DPPH·, ·ABTS+, ·O2-, ·OH scavenging assays, well ferric reducing power ?-carotene bleaching assays. The results showed that caffeic protocatechuic acid with simple dihydroxylation structures h...

Catalase isozymes of maize (Zea mays, L. hybrid Norma) were shown to differ in their sensitivity to phenolic compounds. Salicylic acid, benzoic acid, acetylsalicylic acid and o-coumaric acid caused significantly greater inhibition of CAT1 activity than of CAT2. The nature of inhibition was non-competitive for CAT1, while CAT2 was inhibited competitively. P-hydroxybenzoic acid (pHBA) was the onl...