Proficient synthesis of biologically active pregnane derivatives and its glycoside – Experimental and theoretical approach

Comprehensive polyoxypregnane glycosides report in Caralluma quadrangula using UPLC-ESI-Q-TOF and their antioxidant effects in human plasma

ETHNOPHARMACOLOGICAL RELEVANCE

Caralluma quadrangula (Forssk.) N.E.Br. (Syns: = Stapelia quadrangula Forssk. = Monolluma quadrangula Forssk.) is an indigenous member of the genus Caralluma and it is a rather common species on rocky hillsides in the southwestern part of Saudi Arabia. Several members of this genus have found medicinal uses in the treatment of rheumatism, diabetes, leprosy and as antiseptics and disinfectants. All parts are edible but rather more bitter and can cause diarrhea.

AIM OF THE STUDY

The present report was tentatively elucidated the structure of acylated and non-acylated polyoxypregnane glycosides from Caralluma quadrangula.

MATERIALS AND METHODS

The analyses were performed using an electrospray-ionization quadrupole time-of-flight (ESI-Q-TOF) mass spectrometer in both positive and negative ionization modes to explore fragmentation pathways. The antioxidant and prooxidant properties of the different mobility portions of human plasma were evaluated in vitro using thiobarbituric acid reactive substance assay (TBARS).

RESULTS

The analyses showed sixty-five characteristic ion peaks which could be more efficient to assignment the aglycones and fragmentation sequences of sugar moieties. The used ionization modes provided consistent and/or complementary information for most of the pregnane glycosides, their fragmentation sequences, and their aglycones. A DFT Study was performed to elucidate the neutral loss of H₂O molecules sequences from aglycones and the esterification linkage.

CONCLUSIONS

This report could be useful to reduce material consuming and time in phytochemistry analysis of the different medicinal plants. The two portions significantly depleted TBARS were subjected to autoperoxidation assay in the presence of hydrogen peroxide.

Design, synthesis, and biological activities of novel thiophene, pyrimidine, pyrazole, pyridine, coumarin and isoxazole: Dydrogesterone derivatives as antitumor agents

On the basis of our consideration to design and to develop antitumor activities of heterocyclic compound derivatives, especially in fused ring system, we refer to the possibility of the heterocyclic extension of one of the most important steroid compounds used as a medicinal drug. The reaction of dydrogesterone with each of the malononitrile or ethylcyanoacetate containing elemental sulfur afforded thiophene derivatives 1a,b. Also, dydrogesterone was reacted with a mixture of ethylcyanoacetate–hydrazine, ethylcyanoacetae–urea, or ethylcyanoacetate–thiourea to produce pyrazole derivative 4 and pyrimidine derivatives 5a,b. Thienopyrimidine derivatives 2a–d were introduced from the reaction of thiophene derivatives 1a,b with either phenylisothiocyanate or benzoylisothioyanate. Furthermore, compounds 1a,b were directed toward the reaction with ethylcyanoacetate to produce compounds 6a,b, and the last compounds 6a,b were directed toward cyclization to obtain thienopyridine derivatives 7a,b. In addition, compounds 6a,b were subjected to react with different carbonyl compounds, such as salicylaldehyde, cyclopentanone-elemental sulfur, malonaldehyde, and acetylacetone to produce coumarin derivatives 8a,b, fused thiophene derivatives 9a,b, and pyridine derivatives 10a–d. Isooxazole derivatives 12a,b were afforded through the reaction of compounds 6a,b with hydroxylamine hydrochloride. Finally, 2-pyridone derivatives 14a,b were obtained through the reaction of compounds 6a,b with benzoylacetonitrile. Conformation structure of the synthesized compounds was established by applying IR, 1H NMR, 13C NMR, and mass spectrometry, and their antitumor activity was examined. Some compounds showed promising growth inhibitory effects on the three different cell lines.

A new pregnane glycoside from Gomphocarpus fruticosus growing in Egypt

Phytochemical investigation of Gomphocarpus fruticosus (L.) Ait. of Egyptian origin afforded the new pregnane glycoside lineolon-3-O-[β-D-oleandropyranosyl-(1-4)-β-D-cymaropyranosyl-(1-4)-β-D-cymaropyranoside], along with six known compounds. The structures of the isolated compounds were elucidated on the basis of extensive spectroscopic evidences derived from 1D, 2D NMR experiments, mass spectrometry and by comparing their physical and spectroscopic data to literature. These included the triterpenoids 3β-taraxerol, 3β-taraxerol acetate and betulinic acid, which are identified for the first time in G. fruticosus and the cardenolides uzarigenin, gomphoside and calotropin.