"LICKOR mixtures of organolithium reagents and bulky potassium alcoholates allow the smooth metalation and subsequent electrophilic substitution of low acidity hydrocarbons, in particular olefm. The allylpotassium intermediates exhibit peculiar conformational preferences which can be exploited in novel stereoselective carbon-carbon linking reactions. A few syntheses of simple natural products i...

Unprecedented tetracyclic polymer topologies with spiro- and a bridged-type quatrefoil forms are effectively constructed through an alkyne-azide, click-linking reaction by employing a kyklo-telechelic poly(tetrahydrofuran), poly(THF), precursor having an azide group, obtained through an electrostatic self-assembly and covalent fixation (ESA-CF) process, and complementary tetrafunctional alkyne ...

Site-directed photoaffinity cross-linking experiments were performed by using human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) mutants with unique cysteine residues at several positions (i.e., positions 65, 67, 70, and 74) in the fingers subdomain of the p66 subunit. Since neither the introduction of the unique cysteine residues into the fingers nor the modification of the...

the purpose of this investigation was to develop a simple colorimetric method for creatine kinase (ck). the new method is based on the reaction of creatine, formed enzymatically from creatine phosphate and adp, with different glyoxal compounds. hydrated glyoxals, such as para-nitrophenyl, 2-thiophene, 4- biphenyl, 4, 4' -biphenyl,α-naphthyl, β-naphthyl, para-chlorophenyl, and styryl were s...

Plasmids encoding "split" lactose permease constructs with discontinuities in either the periplasmic loop between helices V and VI (N(5)/C(7)) or between helices VI and VII (N(6)/C(6)) were used to localize helix VI within the tertiary structure by site-directed thiol cross-linking. A total of 57 double-Cys pairs, with one Cys residue in helix VI and another in helix V or VIII, were studied wit...