Treatment of acetyl- 1,4-benzoquinone with isoprene gave the corresponding regioselective adduct (I). Rearrangement of the adduct (1) in pyridine and methanol gave 2-acetyl-5, 8-dihydro-6-methyl- 1,4-dihydroxynaphthalene (2). Silver oxide oxidation of the rearranged product (2) gave 2-acetyl-5,8-dihydro- 6-methyl- 1,4naphthalenedione (3). Regioselective addition of trans-piperylene to this...

treatment of acetyl- 1,4-benzoquinone with isoprene gave the corresponding regioselective adduct (i). rearrangement of the adduct (1) in pyridine and methanol gave 2-acetyl-5, 8-dihydro-6-methyl- 1,4-dihydroxynaphthalene (2). silver oxide oxidation of the rearranged product (2) gave 2-acetyl-5,8-dihydro- 6-methyl- 1,4naphthalenedione (3). regioselective addition of trans-piperylene to this comp...

objective: with consideration of lethal effects of aflatoxins specially b1 on human health. estimation of aflatoxin-albumin adduct, as an important marker of aflatoxin exposure, seems essential. the aim of this study is optimization of hplc-fluorescence method for measurement of this important marker in blood serum. materials and methods: in this study, blood serum of three groups of rats as a...

the equilibrium constant of adduct formation between some triorganotin chloride of the type r3sncl (r=c6h5, p-ch3c6h4, n-ch3)ch2)3, c6h5-ch2 and lewis bases cl¯, br¯, and i¯, were measured in 50% v/v ethanol-water solvent spectrophotometrically. the average equilibrium constant values for the systems studied shows the following acceptor trend of tin(iv) in the triorganotin chlorides: p-tolyl > ...

mgcl2/c2h5oh adducts with constant relative ratio of 1/3 were prepared and kept at 120oc for different lengths of times of 5, 10, 20, 30, 50, 90,120 and 220 h. then the samples were quenched and analyzed by xrd and bet. no meaningful changes were observed in the specific surface area of the samples, while xrd spectra showed 3 peaks at 2θ<15o for samples kept at 120oc for 5 h. these 3 peaks were...

Primary MgCl2.3.3EtOH adduct (PCT1) was prepared by melt quenching method and then submitted into a programmed thermal dealcoholation project using a fluidized bed reactor. During thermal dealcoholation program, different MgCl2.nEtOH support samples with n= 3.0, 2.7, 2.4, and 2.1 were selected and named as PCT2 to PCT5, respectively. Structural analysis of the support samples showed a significa...

The formation constants and Gibbs free energy for the interaction of RnSnClm (n = m = 2, R = Me, Ph, n-Bu or n = 4, m = 0, R = Ph) compounds as acceptors, with ML complexes (H2L = N,N'-bis(salicylidene)-2-aminobenzylamine (salabza-H2) and its derivatives, M = Mn2+ or Zn2+), as donors in N,N'-dimethylformamide (DMF) as solvent were studied. These parameters were measured by using UV-vis spectrop...

primary mgcl2.3.3etoh adduct (pct1) was prepared by melt quenching method and then submitted into a programmed thermal dealcoholation project using a fluidized bed reactor. during thermal dealcoholation program, different mgcl2.netoh support samples with n= 3.0, 2.7, 2.4, and 2.1 were selected and named as pct2 to pct5, respectively. structural analysis of the support samples showed a significa...

Two biomarkers of exposure to cigarette smoke, 4-aminobiphenyl-hemoglobin (Hb) adducts and aromatic DNA adducts in lymphocytes, were determined from a population of 55 smokers and 4 nonsmokers. The levels of these adducts were related to daily cigarette consumption and also to (calculated) tar and nicotine intake. The Hb adduct levels seemed to correspond best to the number of cigarettes (cig) ...

The causative role of polycyclic aromatic hydrocarbons (PAH) in human carcinogenesis is undisputed. Measurements of PAH-DNA adduct levels in easily accessible white blood cells therefore represent useful early endpoints in exposure intervention or chemoprevention studies. The successful applicability of DNA adducts as early endpoints depends on several criteria: i. adduct levels in easily acces...