Abrusamide A and B, two hepatoprotective isomeric compounds from Abrus mollis Hance

Hydroxycinnamoyl Amino Acids Conjugates: A Chiral Pool to Distinguish Commercially Exploited Coffea spp.

“…[ ] -33.2 (c 1.0, MeOH) As can be seen in Figure 3, all mass spectra of HCAs 1b-5b present, besides the quasi molecular ion, an intense peak at higher m/z ratio, which can be attributed to a dimer that is formed during ionization. The structure of the dimer formed from 1b is reported in Figure 4 and the assignment of this structure is based on what was found by Yuan et al in 2014 [8], who isolated these compounds from Abrus mollis Hance. Analogues dimers can be expected from the other cinnamoyl amides as confirmed by their m/z value.…”

“…Hydroxycinnamic acids can be esterified with quinic acid forming the class of chlorogenic acids, esterified with monosaccharides forming the cinnamoyl glycosides, or can give origin to amides with different amino acids, named hydroxycinnamoyl amides (HCAs) or N-phenylpropenoyl-amino acids. The hydroxycinnamoyl acids are usually conjugated with the amino acids phenylalanine, tyrosine, tryptophan, or aspartic acid, and although their role in the plant is not known, they exhibit biological activity, such as anti-neuroinflammatory activity [7], hepatoprotective activity [8], HIV-1 integrase inhibitors [9], and antidiabetic effects [10]. Moreover, from a sensory point of view, HCAs have been indicated as possible contributors to the sensory properties of some food [11].…”

Synthesis of esters of diaminotruxillic bis-amino acids by Pd-mediated photocycloaddition of analogs of the Kaede protein chromophore

“…The NMR characterization of 2a-j showed that they are obtained as single isomers. The oxazolone exocyclic C=C bond has the (Z)-configuration, because the signal assigned to the C=O group appears as a doublet in the proton-coupled 13 C NMR spectrum, with a 3 J CH coupling constant of 5.6 Hz [50]. In contrast, the C=C bond of the styryl group has an (E)configuration, as inferred from the observation of a 3 J HH coupling constant of 16 Hz between the two olefinic protons of the styryl fragment.…”

“…Moreover, alternative mechanisms to explain the antinociception of truxillic compounds have also been reported [11,12] and have generated intense debate. In addition, truxillic derivatives have shown remarkable activity as hepato-protective agents [13] and they also have applications as internal donors in Ziegler-Natta catalysts for polymerization [14] or as building blocks in polymer chemistry [15].…”

Structural Characterization and Hepatoprotective Activity of Naphthoquinone From Cucumis bisexualis

“…We report here on the isolation and structural elucidation of 3 new naphthoquinones (1-3), together with 10 known naphthoquinone derivatives (4-13) that were isolated from the active fraction (EtOAc layer) of C. bisexualis for the first time ( Figure 1). Moreover, the hepatoprotective activities of compounds (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13) 7 , 469.1287) in the high resolutionelectrospray ionization-mass spectrometry (HR-ESI-MS) data, which requires 18 degrees of unsaturation. The UV spectrum showed absorptions at λ max 210, 232, 280, and 431 nm, suggesting the presence of the naphthoquinone skeleton in compound 1.…”