With the aid of density functional calculations, it was revealed that neuraminidase (NA) inhibitors (Scheme 1) exist exclusively in the neutral form. However, the docking and molecular dynamics simulations indicated that the zwitterionic, rather than neutral, isomers are the active form in NA-receptors. The neutral and zwitterionic isomers of BA (Compound 7 in Scheme 1) are quite different in s...

Variable-temperature lH NMR spectroscopy of the region between 13 and 16 ppm can be used in the conformational analysis of hydrogen-bonded aggregates comprising 1 equiv-of a trismelamine (hub(M)s) and 3 equiv of an isocyanuric acid (CA). T*o typer of isomersare obsenred: a symmetric C3 isomer (identified by two lines in this spectral region at low temperature) and an asymmetric C1 isomer (ident...

Photochromic nucleosides were designed that combine the structural features and molecular recognition properties of nucleic acids with the light-sensitivity of diarylethenes. Target compounds 1a-c consist of a 7-deazaadenosine unit that is linked to a thiophene as the second aryl functionality via a 1,2-cyclopentenyl linker. These nucleoside analogues undergo a reversible electrocyclic rearrang...

Abstract Expansions of CAG/CTG trinucleotide repeats in DNA are the cause at least 17 degenerative human disorders, including Huntington’s Disease. Repeat instability is thought to occur via formation intrastrand hairpins during replication, repair, recombination, and transcription though relatively little known about their structure dynamics. We use single-molecule Förster resonance energy tra...

The structure and biological activities of two disulphide isomers of a C-region deletion mutant of insulin-like growth factor-I (IGF-I) which has an Asn--Gly link engineered at the junction of the A- and B-regions were studied before and after chemical cleavage. Circular dichroism (CD) spectra and binding affinity to IGF binding protein 3 (IGFBP3) indicated that the treatment with hydroxylamine...

In the title compound, [Sb(C(9)H(12)N)(2)Cl], the Sb atom adopts a Ψ-trigonal-bipyramidal geometry. The two 2-[(dimethyl-amino)-methyl]-phenyl ligands are coordinated asymmetrically to the Sb atom. The carbon atoms of one of the ligands are disordered over sets of sites with equal occupancy, resulting in two conformational isomers in the crystal. The Sb-C and Sb-N distances in the ordered ligan...

Positional isomers of naturally occurring peptide subunits were synthesized via highly diastereoselective reduction of tert-butylsulfinyl ketimines as a key reaction. While NaBH4 reduction of ketimines derived from 2-thiazolyl ketones afforded the (RS,R)-isomer with moderate diastereoselectivity, L-Selectride® reduction afforded the (RS,S)-isomer as the sole product. In contrast, ketimines deri...

Schlenk, F. (Argonne National Laboratory, Argonne, Ill.), and J. L. Dainko. Action of ribonuclease preparations on viable yeast cells and spheroplasts. J. Bacteriol. 89:428-436. 1965.-Recrystallized pancreatic ribonuclease releases more than half of the ultraviolet-absorbing cellular constituents of Candida utilis and Saccharomyces cerevisiae. The presence of salts and buffer interferes with th...