6153-09-9Relevant academic research and scientific papers
Chemical transformations and biological studies of terpenoids isolated from essential oil of Cyperus scariosus
Sharma,Utreja,Bedi
, p. 2153 - 2158 (2016/07/20)
Cyperus scariosus is a potential medicinal herb belonging to the family Cyperaceae. The GC-MS analysis of the oil showed cyprene (18.57 %) as the major terpene present in it. Cyprene was isolated from the non-polar fraction of the oil using hexane as solvent and characterized using TLC and spectral techniques (IR and 1H NMR). Cyprene was derivatized to cyprene epoxide by two methods i.e. using perbenzoic acid and epichlorohydrin. Further, the oil, it's polar fraction (dichloromethane), non-polar fraction (hexane), cyprene and cyprene epoxide were screened for their plant growth regulating property in case of wheat seedlings (HD 2967 and PBW 621). Complete germination was observed above 2.5 μg/mL of all the test fractions in both the cultivars. Moreover, cyprene epoxide was found to be the most effective in enhancing the length of roots and shoots. Seedling vigour index was calculated in order to analyze the enhancement shown by the oil and its various components on the seedlings.
Effect of modification of the electrophilic center on the α effect
Um, Ik-Hwan,Lee, Ji-Youn,Bae, Sun-Young,Buncel, Erwin
, p. 1365 - 1371 (2007/10/03)
We report on a nucleophilic study of esters R-C(=X)-Y-Ar in which the electrophilic center has been modified by replacing O by S in the leaving group or carbonyl center: 4-nitrophenyl acetate (1), S-4-nitrophenyl thioacetate (2), 4-nitrophenyl benzoate (3), and O-4-nitrophenyl thionobenzoate (4). The studies include O- and S- nucleophiles as well as α nucleophiles in H2O at 25.0 ± 0.1°C. The sulfur nucleophile (4-chlorothiophenoxide, 4-ClPhS-) exhibits significant enhanced reactivity for the reactions with thiol and thione esters 2 and 4 compared with their oxygen analogues 1 and 3. On the contrary, the common nucleophile OH- is much less reactive towards 2 and 4 compared with 1 and 3. The effect of changing both the electrophilic center and the nucleofugic center on the reactivity of the other oxygen nucleophiles is not so significant: 4-chlorophenoxide (4-ClPhO-) is four to six times more reactive in the reactions with thiol and thione esters 2 and 4 compared with their oxygen analogues 1 and 3. The α effects exhibited by butan-2,3-dione monoximate (Ox-) and HOO- are strongly dependent on the nature of the electrophilic center of the substrates, indicating that the difference in the ground-state solvation energy cannot be fully responsible for the α effect. Our results clearly emphasize the strong dependence of the α effect on the substrate structure, notably, the nature of the electrophilic center. The impact of change in the nucleofuge (1-→2) and the electrophilic center (3-→4) on reactivity indicates that anucleophiles will need to be "purpose built" for decontamination and nucleophilic degradation of specific biocides.
