Alkaloid Constituents ofSida acuta,S. humilis,S. rhombifoliaandS. spinosa*

Abstract

Three types of alkaloidal constituents, viz., beta-phenethylamines, quinazolines and carboxylated tryptamines, in addition to choline and betaine have been isolated from Sida acuta Burm., S. humilis Willd., S. rhombifolia L., and S. spinosa L. and characterized by their physical and spectral properties, and by chemical transformations. The qualitative and quantitative variations in the alkaloidal constituents of roots and aerial portions at different stages of growth were also noted. Elaboration of the quinazoline alkaloids seems to be a characteristic feature of this genus. The favourable combination of sympathomimetic amines and vasicinone in these species would account for their major therapeutic uses in the Indian system of medicine.

Genetic and Chemical Diversity of High Mucilaginous Plants of Sida Complex by ISSR Markers and Chemical Fingerprinting

“…Further analysis of HPTLC images as reported by Khatoon et al [2] and Jadhav et al [20] along with the present investigation, no conclusive chemical patterns except for S. acuta was drawn. While analyzing the alkaloids in Sida species [21], the presence of vasicine and absence of cryptolepine in S. acuta, which was contradictory to the earlier report [22] indicating that the chemical variability may be driven by environmental conditions prevailing at the time and stage of sampling and their habitat. But on the other hand, in connection with other approaches, analyses of chemical constituents can greatly help to clarify problems of species, speciation, and evolution [23].…”

Anti-hyperglycemic, antioxidant, and anti-inflammatory activities of extracts and metabolites from Sida acuta and Sida rhombifolia

“…Additionally, the presence of the singlet signal of a methyl group at δ H 1.95, and the resonances of a carbonyl carbon at δ C 172.7 and a methyl at δ C 22.4 indicated an acetyl group which was located at C-25 (δ C 83.9) by comparing its chemical shift with those reported in the literature. 15 Compound 11 spectroscopic features were in agreement with 25-acetoxy-20-hydroxyecdysone 3-O-β-D-glucopyranoside, previously isolated from S. rhombifolia. 13 In previous reports, a slight reduction on blood glucose level in normal glycemic rats produced by the methanolic extract of leaves of S. acuta has been stablished, 5 and a dose-dependent anti-hyperglicemic effect induced on diabetic rats by the methanolic and aqueous extracts of S. rhombifolia related to their antioxidant properties, was pointed out.…”

“…8 As a result of the abundant activities of these plants there are also many pharmacological evaluations; their analgesic, 9 antidiarreic, 10 anti--oxidant, vasorelaxant, 11 and anti-hyperglycemic activities, 12 among others, have been tested, mainly from extracts of different species. 7 Previous chemical reports show the presence of ecdysteroids, 13,14 alkaloids, 11,15 and flavonoids, 11,16 as main secondary metabolites in S. acuta and S. rhombifolia.…”

Evaluation of Antibacterial Activities of Compounds Isolated From Sida rhombifolia Linn. (Malvaceae)

“…The dichloromethane soluble fraction also revealed potent antioxidant activity [40]. Isolation and characterization of alkaloid constituents such as β-phenethylamine, ephedrine, ψ-ephedrine, quinazoline such as vasicine, vasicinol, vasicinone, carboxylated tryptamines such as S-(+)-N b -methyltryptophan methyl ester, choline and betaine from aerial Sida rhombifolia were reported by Prakash et al [41]. Sterols (β-sitosterol, stigmasterol, campesterol, stigmasterol, spinasterol and cholesterol), n-alkanes (e.g., nonacosane and hentriacontane) and n-alcohols were also identified/reported from dried whole and aerial parts of Sida rhombifolia [37,[42][43][44].…”