An analytical technique has been developed for the determination of methylmercury compounds in environmental samples. The technique is based on a two-stage procedure. In the first stage, methylmercury compounds are isolated from the sample matrix as methylmercury chloride (MeRgCl) by distillation. The distillation procedure is based on a series of...
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...
The first part of this manuscript is about the total synthesis of the aspidosperma alkaloids leuconoxine, melodinine E and mersicarpine. Our synthetic strategy used a radical translocation-conjugate addition cascade to construct the core of the natural product. Specifically, a vinyl radical was generated from the homolysis of the C–I bond...
Theoretical studies and experimental results are presented for the rotational motion of molecule's in crystalline solids. The group theory is solved for molecules of any symmetry matrix isolated at a site in a crystal field of any symmetry. As the potential terrier to rotation of the molecule relative to the...
The unique reaction between 4, 6-dimethoxy-5-nitropyrimidine
and methylhydrazine was investigated. The reaction product was
identified as 4-hydrazino-6-hydroxypyrimidine from (a) spectral
data, (b) by direct synthesis of the product via 4-chloro-6-hydroxypyrimidine
and hydrazine, and (c) by conversion of the product to
the known 4-amino-6-hydroxypyrimidine using Raney nickel. The
product was not...
The yields of 235 projectile-like and target-like fragments from the interaction of ¹³⁶Xe with a thick target of ²⁰⁸Pb at a center-of-mass energy, E[subscript cm], of 450 MeV were measured using γ-γ-γ coincidence data from Gammasphere and off-line γ-ray spectroscopy. The results give an expansive picture of the production cross...