Zobrazeno 241 - 250
of 469
pro vyhledávání: '"35"'
Publikováno v:
Journal of the American Chemical Society. 120:1124-1132
A disulfide-bridged two-stranded α-helical coiled-coil peptide has been designed which undergoes a random coil to α-helical transition at pH 7 and 20 °C upon metal binding to two sites engineered into the molecule. The metal binding coiled-coil, d
Publikováno v:
Journal of the American Chemical Society. 119:12192-12200
The two available crystallographic structures of cobalamin dependent enzymes, the 27 kDa fragment of the methylcobalamin-dependent enzyme, methionine synthase, from Escherichia coli [Drennan, C. L. et al. Science 1994, 266, 1669] and the 5‘-deoxyad
Publikováno v:
Journal of the American Chemical Society. 119:12159-12169
The synthesis of (−)-stipiamide (1) is reported together with the designed enynes 2 (6,7-dehydrostipiamide) and 3 that are now shown to reverse the multidrug resistance (MDR) of human breast cancer cells (MCF-7adrR). Stipiamide was assembled using
Publikováno v:
Journal of the American Chemical Society. 119:9662-9671
A practical route for the total synthesis of 8,9-secokaurene diterpenes is described. The central step is the [3.3]sigmatropic rearrangement of spirocyclic intermediates such as 35, 40, and 41. All three compounds must necessarily respond identically
Autor:
Donald J. Burton, Haridasan K. Nair
Publikováno v:
Journal of the American Chemical Society. 119:9137-9143
Under UV irradiation (254 nm) at ambient temperature, a degassed mixture of (EtO)2POP(OEt)2 and RfI {Rf = CF3, C2F5, C4F9, C6F13, (CF3)2CF, CF2CFCF2, ClCF2CF2, BrCF2CF2, C6F5, ClCF2CFClCF2CF2, I(CF2)3, I(CF2)4, FO2S(CF2)4, FO2S(CF2)2O(CF2)2} affords
Publikováno v:
Journal of the American Chemical Society. 119:9810-9815
It was found that perfluoropolyethers (PFPE) with carboxylic acid end groups, PFPE-COOH, and their sodium salts, PFPE-COONa, afford an anhydrous fluid medium in which the direct pair-wise interaction of these end groups may be examined. An IR study (
Publikováno v:
Journal of the American Chemical Society. 119:10439-10445
Formation of ML+ and ML2+ complexes of coronene was investigated with 25 atomic ions (M+) in the low-pressure gas-phase environment of the Fourier-transform ion cyclotron resonance (FT-ICR) ion trapping mass spectrometer. All of the atomic ions forme
Publikováno v:
Journal of the American Chemical Society. 119:10121-10126
The resting state of nitrogenase shows an S = 3/2 electron paramagnetic resonance (EPR) signal resulting from the FeMo-cofactor (MoFe7S9:homocitrate) of the MoFe protein. When the enzyme undergoes turnover under a CO atmosphere, this signal disappear
Publikováno v:
Journal of the American Chemical Society. 119:8852-8856
Soluble silica reduces aluminum availability and ameliorates toxicity in several biological systems. It has therefore been suggested that these two species strongly interact in solution. However, there is only weak affinity between monomeric silicic
Publikováno v:
Journal of the American Chemical Society. 119:7440-7451
Irradiation of DNA with UV-B light causes the formation of mutagenic DNA lesions such as cis−syn and trans−syn cyclobutane pyrimidine dimers. DNA photolyases are flavin-dependent repair enzymes which directly revert the mutagenic cis−syn pyrimi