Recently, a series of potent and selective neuronal nitric oxide synthase inhibitors containing two basic nitrogen atoms was reported (Ji, H.; Stanton, B. Z.; Igarashi, J.; Li, H.; Martásek, P.; Roman, L. J.; Poulos, T. L.; Silverman, R. B. J. Am. Chem. Soc. 2008, 130, 3900 3914).
Atoms are reported to be engaged in short contacts, if their spatial distance at the interface is lesser than the allowed van der Waals distance.
It has been suggested that DSSP can miss the elucidation of edge strands (Martin et al., 2005) and has difficulties dealing with low resolution structures (Martin et al., 2005) and with structures where only the Cα trace atoms are reported (Labesse et al., 1997).
The synthesis and X-ray crystallographic characterization of diphenylglycoluril derivatives (1 4) that possess one or two alkyl groups on their N- or O-atoms is reported.
However, for guillemot eggs from Iceland, the Faroer Islands, and Norway [84]; herring gull eggs from northern Norway [83]; and ivory gull eggs from the Russian and Norwegian Arctic [71], a predominance of longer-chain PFCA with > 8 C-atoms was reported although concentration levels varied strongly.
The angle at the oxygen atom was reported as 110°, whereas the Br-Br-O angles were strictly linear.
In compound 18, 5-S-allyl protons were interpreted with the same splitting pattern but highly deshielded at 6.04, 5.42, 5.20 and 4.09 by higher electronegativity of S-atom and their 13C-signals were reported at 129.6 (C-2″), 115.1 (C-3″), and 32.1 (C-1″).
Data were reported as atom percent excess (APE).
No positions were reported for the H atoms. Two alternatives are possible for the infinite chain of hydrogen bonds.
