Showing papers by "Islamic Azad University North Tehran Branch published in 2003"
TL;DR: In this article, a tetradentate Schiff base ligand was derived from the phenolic oxygen and azomethine nitrogen, and the results indicated that the Schiff base is a bivalent anion with tetralentate ONNO donors.
Abstract: New Mn(II), Co(II), Ni(II) and Cu(II) complexes of a tetradentate Schiff base ligand [bis(2-hydroxyanil)acetylacetone],“2-[{1-methyl-3-[(2-hydroxyphenyl)imino]butylidene}amino]phenol”, H 2 haacac, have been prepared and characterized by elemental analyses, IR and conductometry. The results suggest that the Schiff base is a bivalent anion with tetradentate ONNO donors derived from the phenolic oxygen and azomethine nitrogen. The formulae was found to be [M(haacac)] for the 1:1 non-electrolytic complexes. Alumina-supported [M(haacac)] complexes catalyze the oxidation of cyclohexene with tert -butylhydroperoxide (TBHP). The major products of the reaction were 2-cyclohexene-1-ol (OH), 2-cyclohexene-1-one (CO) and 2-cyclohexene-1-( tert -butylperoxy) (OO t Bu). The influence of temperature, solvent and time for the oxidation reaction has been studied. The selectivity of 2-cyclohexene-1-( tert -butylperoxy) varied with reaction temperature. Mn(haacac)-alumina shows significantly higher catalytic activity than other alumina-supported complexes.
149 citations
TL;DR: Both oils were richer in oxygenated monoterpenes than sesquiterpenes, and the oil of S. acerosa was characterized by higher amounts of cis-chrysanthenyl acetate and linalool, which were among the 20 components comprising 92.1 % of the total oil detected.
Abstract: The oil obtained by hydrodistillation of the aerial parts of Stachys pilifera Benth. and Stachys acerosa Boiss., which are endemic to Iran, was analyzed by GC/MS. Thirty compounds representing 88.9% of the oil of S. pilifera were identified, among them cis-chrysanthenyl acetate (25.2%) and trans-verbenol (19.7%) being the major ones. The oil of S. acerosa was characterized by higher amounts of cis-chrysanthenyl acetate (41.0%) and linalool (23.5%), which were among the 20 components comprising 92.1 % of the total oil detected. Both oils were richer in oxygenated monoterpenes than sesquiterpenes.
29 citations
TL;DR: The essential oil of the aerial parts of Achillea albicaulis C.A. was analyzed by capillary GC and GC/MS as discussed by the authors, and the major constituents were 1-8-cineole (10.1%), camphor (9.2%), germacrene D (7.8%), piperitone (6.2), α-pinene (5.9%), and artemisia ketone (57%).
Abstract: The essential oil of the aerial parts of Achillea albicaulis C.A. Mey. was analyzed by capillary GC and GC/MS. The major constituents were 1,8-cineole (10.1%), camphor (9.2%), germacrene D (7.8%), piperitone (6.2%), α-pinene (5.9%) and artemisia ketone (5.7%).
13 citations
TL;DR: A hydrodistilled oil of the aerial parts of Lomatopodium khorassanicum Mozaffarian (Umbelliferae), an endemic species of Iran, has been analyzed by GC/MS and the major components were found to be myrcene, (E)-β-ocimene and limonene.
Abstract: A hydrodistilled oil of the aerial parts of Lomatopodium khorassanicum Mozaffarian (Umbelliferae), an endemic species of Iran, has been analyzed by GC/MS. The major components were found to be myrcene (28.2%), (E)-β-ocimene (15.4%) and limonene (10.1%).
6 citations
TL;DR: In this article, the unsymmetrical twist-chair (TC) conformation was calculated to be the most stable conformation of 1.7 kJ mol−1.
Abstract: Ab initio calculations at HF/6-31+G* level of theory for geometry optimization and MP2/6-31+G*//HF/6-31+G* level for a single point total energy calculation are reported for lenthionine (1,2,3,5,6-pentathiepane) (1). The unsymmetrical twist-chair (TC) conformation was calculated to be the most stable conformation of 1. The unsymmetrical twist-boat (TB) form was found to be 33.0 kJ mol−1 less stable. Conformational racemization of TC can take place via plane symmetrical chair geometry as transition state and requires 50.7 kJ mol−1.
5 citations