The two sulfur isotopomers of sulfur trioxide, ³²S¹⁶O₃ and ³⁴S¹⁶O₃, have been studied via high resolution infrared and Coherent anti-Stokes Raman (CARS) spectroscopy. The v₁ symmetric SO stretching Q-branches observed by the latter are quite different, being especially complex for ³²S¹⁶O₃ Understanding this band structure required analysis of infrared-active hot...
Feeding of [3-¹³C, 2-¹⁵N]arginine, 38a, unequivocally established that the β-
arginine moiety of blasticidin S, 1, was formed from α-arginine by an intramolecular
migration of the α-amino group to the β- position. Further feedings using chirally
deuteriated arginines 38e and 38f revealed that the aminomutase process occurred with
inversion of...
Xanthohumol [XN, (E)-6´-methoxy-3´-(3-methylbuten-2-yl)-2´,4´,4´´-trihydroxychalcone], the principal prenylated chalcone from hops, and its 2,3-dihydro- (DXN) and O6-desmethyl-2,3-dihydro- (DDXN) congeners, are of potential utility for the amelioration of metabolic syndrome; however, their complex bioactivity profiles cannot be properly studied and understood without access to appropriately produced synthetic materials.
In the first part of...
Two labelled arginines, DL-[2,3,3,-²H₃]arginine, 8,
and DL-[ ¹³C, 2-¹⁵N]arginine, 9, were synthesized. These
were fed to cultures of Streptomyces griseochromogenes in
order to probe the mechanism of the apparent arginine-2,3-
aminomutase reaction occurring in biosynthesis of blasticidin
S, 1. In previous studies of the enzymes lysine-2,3-
aminomutase and tyrosine-2,3-aminomutase different...
The target fragment production cross sections, angular
distributions, and range distributions have been measured for the
interaction of 12-16 A MeV³² S with ¹⁶⁵Ho. The fragment isobaric
yield distribution and the moving frame angular distributions have
been deduced from the data. Symmetry properties of the moving frame
angular distributions have...