New coumarin derivatives, namely (2-(4-methyl-2-oxo-2H-chromen-7-yloxy)-N-(4-oxo-2-phenylthiazolidin-3-yl)acetamide, N-(2-(3-methoxyphenyl)-4-oxothiazolidin-3-yl)-2-(4-methyl-2-oxo-2H-chromen-7-yloxy)acetamide, 2-(4-methyl-2-oxo-2H-chromen-7-yloxy)-N-(4-oxo-2-(2,3,4trimethoxyphenyl)thiazolidin-3-yl)acetamide and N-(2-(4-bromophenyl)-4-oxothiazolidin-3-yl)-2-(4-methyl-2-oxo-2H-chromen-7-yloxy)ac...

Let D(n) be the maximal determinant for n × n {±1}-matrices, and R(n) = D(n)/n be the ratio of D(n) to the Hadamard upper bound. We give several new lower bounds on R(n) in terms of d, where n = h + d, h is the order of a Hadamard matrix, and h is maximal subject to h ≤ n. A relatively simple bound is R(n) ≥ ( 2 πe )d/2( 1− d ( π 2h )1/2) for all n ≥ 1. An asymptotically sharper bound is R(n) ≥...

Theoretical and experimental studies of the reaction of isoxazoles with diazo compounds show that the formation of 2H-1,3-oxazines proceeds via the formation of (3Z)-1-oxa-5-azahexa-1,3,5-trienes which undergo a 6π-cyclization. The stationary points corresponding to the probable reaction intermediates, isoxazolium N-ylides, were located by DFT calculations at the B3LYP/6-31G(d) level only for d...

The Ni-catalyzed reaction of aromatic amides with alkynes in the presence of KOBu involves C–H/N–H oxidative annulation to give 1(2H)-isoquinolinones. A key to the success of the reaction is the use of a catalytic amount of strong base, such as KOBu. The reaction shows a high functional group compatibility. The reaction with unsymmetrical alkynes, such as 1-arylalkynes, gives the corresponding ...

Plasma glucose 2H enrichment was quantified by 2H NMR in patients with cirrhosis (n=6) and healthy subjects (n=5) fasted for 16 h and given 2H(2)O to approximately 0.5% body water. The percent contribution of glycogenolysis and gluconeogenesis to glucose production (GP) was estimated from the relative enrichments of hydrogen 5 and hydrogen 2 of plasma glucose. Fasting plasma glucose levels were...