RESUMEN
Phytochemical study on the methanol extract of the stems of Tinospora crispa (L.) Hook.f. & Thomson led to the isolation of thirteen compounds including three undescribed cis-clerodane-type furanoditerpenoids (1-3) and ten known ones (4-13). Their chemical structures were determined by IR, HR-ESI-MS, 1D-, and 2D-NMR spectra. Compounds 2-6 and 8 inhibited moderately NO production in LPS activated RAW 264.7 cell with the IC50 values of 83.5, 57.6, 75.3, 78.1, and 74.7 µM, respectively.
RESUMEN
Four undescribed spirostan glycosides, (25S)-5α-spirostan- 12-one-2α,3ß-diol-3-O-ß-D-glucopyranosyl-(1â4)-ß-D-galactopyranoside (1), (25S)-5α-spirostan-12-one-2α,3ß-diol-3-O-ß-D-galatopyranosyl-(1â2)-ß-D-glucopyranosyl- (1â4)-ß-D-galactopyranoside (2), (25S)-5α-spirostan-12-one-2α,3ß-diol-3-O-ß-D-glucopyranosyl-(1â2)-[ß-D-glucopyranosyl-(1â3)]-ß-D-glucopyranosyl-(1â4)-ß-D-galactopyranoside (3), and hecogenin 3-O-ß-D-glucopyranosyl-(1â3)-[ß-D-xylopyranosyl-(1â2)]-ß-D-glucopyranosyl-(1â4)-[α-L-rhamnopyranosyl-(1â2)]-ß-D-galactopyranoside (4), together with eleven known compounds (5-15) were isolated from the branches and leaves of Tribulus terrestris. Their chemical structures were established through spectroscopic methods, including HR-ESI-MS, 1D-, and 2D-NMR spectra. Preliminary biological evaluation on NO production inhibitory activity in LPS activated RAW 264.7â cells showed that compoundsâ 1-3, 5, and 6 had significant inhibitory effects with IC50 values ranging from 2.4 to 18.3â µM, compared to that of the positive control compound, dexamethazone (IC50 13.6â µM).
Asunto(s)
Glicósidos , Lipopolisacáridos , Óxido Nítrico , Hojas de la Planta , Espirostanos , Tribulus , Ratones , Animales , Células RAW 264.7 , Lipopolisacáridos/antagonistas & inhibidores , Lipopolisacáridos/farmacología , Tribulus/química , Hojas de la Planta/química , Glicósidos/química , Glicósidos/farmacología , Glicósidos/aislamiento & purificación , Óxido Nítrico/antagonistas & inhibidores , Óxido Nítrico/biosíntesis , Espirostanos/química , Espirostanos/aislamiento & purificación , Espirostanos/farmacología , Tallos de la Planta/química , Relación Estructura-ActividadRESUMEN
BACKGROUND: Sydnone is a heterocycle that exhibits remarkable pharmacological activities, including antimicrobial, anti-inflammatory, analgesic, antipyretic and antioxidant activities. Thiosemicarbazones are of compounds that contain the -NHCSNHN=C< linkage group and are considerable interest because they exhibit important chemical properties and potentially beneficial biological activities. Similarly, thiosemicarbazones having carbohydrate moieties also exhibit various significant biological activities. RESULTS: The compounds of 3-formyl-4-phenylsydnones were obtained by Vilsmeyer-Haack's formylation reaction and were transformed into thiosemicarbazones by condensation reaction with N-(2,3,4,6-tetra-O-acetyl-ß-d-glucopyranosyl)thiosemicarbazide. Reaction were performed in the presence glacial acetic acid as catalyst using microwave-assisted heating method. Reaction yields were 43â85 %. The antimicrobial activities of these thiosemicarbazones were screened in vitro by using agar well diffusion and MIC methods. Among these thiosemicarbazones, compounds 4k, 4l, 4m and 4n were more active against all tested bacterial strains, especially against S. epidermidis, B. subtilis and E. coli. The MIC values in these cases are 0.156, 0.156 and 0.313 µg/mL, respectively. All compounds showed weak to moderate antifungal activity against C. albicans and A. niger than nystatin (MIC = 0.156â0.625 µg/mL vs. MIC = 0.078 µg/mL of nystatin), and thiosemicarbazones 4l, 4m and 4n exhibited significant activity with MIC = 0.156 µg/mL. These compounds also had good antifungal activity against F. oxysporum similarly to nystatin (MIC = 0.156 µg/mL). Among the tested compounds having halogen group 4k, 4l, 4m and 4n showed highest activity against three strains of fungal organisms. CONCLUSIONS: In summary, we have developed a clean and efficient methodology for the synthesis of novel thiosemicarbazone derivatives bearing sydnone ring and d-glucose moiety; the heterocyclic and monosaccharide system being connected via âNHâC(=S)NHâN=C< linker using molecular modification approach. The methodology could be further extended and used for the synthesis of other thiosemicarbazones of biological importance. 4-Formyl-3-arylsydnone N-(2,3,4,6-tetra-O-acetyl-ß-d-glucopyranosyl)thiosemicarbazones have been synthesized under microwave-assisted heating conditions. Almost all obtained compounds showed remarkable activities against the tested microorganisms. Among the tested compounds having halogen group 4k, 4l, 4m and 4n showed highest activity against all tested strains of bacterial and fungal organisms. Graphical abstract:Synthesis and antibacterial and antifungal activities of N-(tetra-O-acetyl-ß-D-glucopyranosyl)thiosemicarbazones of substituted 4-formylsydnones.