Search Results (8)

A group of sulfonium and selenonium salts bearing diverse benzylidene acetal substituents on their side chain moiety were designed and synthesized. Compared with our previous study, structural modifications in this study focused on multi-substitution of the phenyl ring and bioisosteric replacements at the sulfonium cation center. In vitro biological evaluation showed that selenonium replacement could significantly improve their α-glucosidase inhibitory activity. The most potent inhibitor 20c (10.0 mg/kg) reduced postprandial blood glucose by 48.6% (15 min), 52.8% (30 min), and 48.1% (60 min) in sucrose-loaded mice, outperforming acarbose (20.0 mg/kg). Docking studies of 20c with ntMGAM presented a new binding mode. In addition to conventional hydrogen bonding and electrostatic interaction, amino residue Ala-576 was first identified to contribute to binding affinity through π-alkyl and alkyl interactions with the chlorinated substituent and aromatic ring. The selected compounds exhibited a high degree of safety in cytotoxicity tests against normal cells. Kinetic characterization of α-glucosidase inhibition confirmed a fully competitive inhibitory mode of action for these sulfonium salts. Full article

This paper presents a methodology for the preparation of a new active component for ion-selective membranes, based on a di-substituted sulfonium derivative of the closo-decaborate anion at the apical vertices with the octadecylalkyl substituents 1,10-B₁₀H₈(S(C₁₈H₃₇)₂)₂. This approach is characterized by physicochemical methods of analysis (11B, 1H, 13C NMR spectroscopy, IR spectroscopy and elemental analysis). The compound obtained is used as an active component of a PVC membrane selective to terbinafine hydrochloride. The sensor developed is highly selective to the drug to be detected, has a linearity range of 4.0 × 10⁻⁸–1.0 × 10⁻² and a detection limit of 1.0 × 10⁻⁸, and can detect terbinafine hydrochloride in the pH range of 3 to 6. Full article

A novel class of chiral sulfonium salts, derived from L- and D-methionine, was designed and successfully employed for the diastereoselective synthesis of epoxy amides. This new methodology of asymmetric epoxidation was exploited for the stereoselective construction of fused polycyclic ethers, which are structural motifs present in a great variety of natural products of marine origin. This methodology proved to be useful for the synthesis of the tricyclic A–C system contained in yessotoxin and adriatoxin, and also in many other related natural products of marine origin belonging to the fused polycyclic ether toxins. Full article

The present work focuses on the reactivity of S,S-bis-ylide 2, which presents a strong nucleophilic character, as evidenced by reactions with methyl iodide and CO₂, affording C-methylated salts 3 and betaine 4, respectively. The derivatization of betaine 4 affords the corresponding ester derivative 6, which is fully characterized by using NMR spectroscopy and X-ray diffraction analysis. Furthermore, an original reaction with phosphenium ions leads to the formation of a transient push–pull phosphino(sulfonio)carbene 8, which rearranges to give stabilized sulfonium ylide derivative 7. Full article

A new series of compounds based on perbrominated disubstituted sulfonium derivatives of the closo-decaborate anion (n-Bu₄N)[2-B₁₀Br₉SR₂] (R = n-Pr, i-Pr, n-Bu, n-C₈H₁₇, n-C₁₂H₂₅, n-C₁₈H₃₇) was obtained, characterised by modern physicochemical methods of analysis. According to the results of an X-ray diffraction study, some of the anions and solvate molecules were disordered. The cations (n-Bu₄N)⁺ and anions [2-B₁₀Br₉SR₂]⁻ were associated via C-H…Br and H…H contacts. In addition, Br…Br interactions between anions were revealed. The role of these contacts was analysed in terms of Hirshfeld surface analysis, QTAIM theory and the NCI method using quantum chemical calculations. An increase in the size of the alkyl R moiety led to significant strengthening of the total energy of H…H interactions. In the case of R = -n-C₁₈H₃₇, a parallel mutual orientation of alkyl moieties was established that was similar to the packing of salts of fatty acids. The nature of C-H…Br and Br…Br interionic interactions was found to be attractive, in contrast to the repulsive nature of intermolecular Br…Br interactions. Full article

Vertebrata lanosa is a red alga that can commonly be found along the shores of Europe and North America. Its composition of bromophenols has been studied intensely. The aim of the current study was therefore to further investigate the phytochemistry of this alga, focusing more on the polar components. In total, 23 substances were isolated, including lanosol-4,7-disulfate (4) and the new compounds 3,5-dibromotyrosine (12), 3-bromo-5-sulfodihydroxyphenylalanine (13), 3-bromo-6-lanosyl dihydroxyphenylalanine (14), 3-(6′-lanosyl lanosyl) tyrosine (15) and 5-sulfovertebratol (16). In addition, 4-sulfo-7-dimethylsulfonium lanosol (7) was identified. While, in general, the dimethylsulfonium moiety is widespread in algae, its appearance in bromophenol is unique. Moreover, the major glycerogalactolipids, including the new ((5Z,8Z,11Z,14Z,17Z)-eicosapentaenoic acid 3′-[(6′’-O-α-galactopyranosyl-β-D-galactopyranosyl)]-1-glycerol ester (23), and mycosporine-like amino acids, porphyra-334 (17), aplysiapalythine A (18) and palythine (19), were identified. Full article

Liver disease, especially liver cancer, has become a threat facing the world. Now, antioxidant products are garnering great attention for the treatment and prevention of many diseases. S-Methyl methionine sulfonium chloride (MMSC) is a methionine derivative and is present in many vegetables and has anti-inflammatory effects and antioxidants. This is the first study aiming to investigate the antitumor activity of the MMSC. This study was carried out on 60 male Wistar albino rats (4–6 weeks old age) and divided into four groups, with the first group as normal control, second group as hepatocarcinoma induced by diethyl nitrosamine and carbon tetrachloride (DEN/CCL4) group, third group as normal rats treated with MMSC, and fourth group as hepatocellular carcinoma (HCC) induced rats treated with MMSC. Our findings revealed that MMSC administration after HCC induction significantly improved (p < 0.05) the liver function biomarkers, including AST, GGT, albumin, globulin, and albumin/globulin ratio (A/G), in comparison with those in the HCC group. Moreover, the histopathological changes of the liver tissue in the HCC group were improved by MMSC treatment. Likewise, the expression levels of tumor necrosis factor-alpha (TNF-α), induced nitric oxide synthase (iNOS), transforming growth factor (TGF-1β), and glypican 3 (GP3) were downregulated by MMSC treatment after HCC induction in comparison with those in the HCC-induced group. In conclusion, MMSC showed antitumor activity against HCC induction by DEN/CCl4 through decreasing lipid peroxide formation, the expression level of an inflammatory cytokines such as (TNF-α), immunoregulatory cytokines such as (TGF-1β), induced nitric oxide synthase, and glypican 3. Full article

The crystal structure of 9-dibenzylsulfide-7,8-dicarba-nido-undecaborane 9-Bn₂S-7,8-C₂B₉H₁₁ was determined by a single-crystal X-ray diffraction. One of the benzyl groups is located above the open face of the carborane cage with a short H···H distance (2.29 and 2.71 Å for two symmetrically independent molecules) between the BHB-bridging hydrogen atom of the carborane fragment and the ortho-CH group of the aromatic ring. Topological analysis has revealed the existence of a critical bond point with a calculated energy of −0.8 kcal/mol in accordance with an X-ray diffraction molecular geometry. The crystal packing analysis revealed that this benzyl group is also involved in π-stacking interactions, while another benzyl group participates in numerous weak H···π, H···H and van der Waals interactions. Full article