Selected developments and trends in stains, labels and strategies for detecting and measuring nucleic acids (DNA, RNA) and related molecules [e.g. oligo(deoxy)nucleotides, nucleic acid fragments and polymerase chain reaction products] are surveyed based on the literature in the final decade of the 20th century (1991-2000). During this period, important families of cyanine dyes were developed fo...

Structure-activity relationships in a series of (5R)-6-triazolylmethylene penems with potent beta-lactamase inhibitory activity are described. In most cases, their in vitro synergistic activity with amoxycillin is superior to that of clavulanic acid, sulbactam and tazobactam (YTR 830). Against an Escherichia coli TEM-1 infection in mice, the compounds showed a broad range of potencies; an optim...

A new N-acyl taurine (1), together with a new natural product, l-(beta-D-ribofuranosyl)-1,2,4-triazole (4), and two known compounds (2 and 3), were isolated from the sea urchin, Glyptocidaris crenularis. The new N-acyl taurine was elucidated as 2-(5R,15S-dihydroxyeicosanoylamino) ethanesulfonic acid on the basis of spectroscopic (NMR, MS) analyses and the modified Mosher ester method. Compound ...

CD spectra for homooligomers (n = 4, 6, 8) of (1S,4R,5R)-5-syn-carboxy-2-azabicyclo[2.1.1]hexane (MPCA), a methano-bridged pyrrolidine β-carboxylic acid, suggest an ordered secondary structure. Even in the absence of internal hydrogen bonding, solution NMR, X-ray, and in silico analyses of the tetramer are indicative of conformations with trans-amides and C(5)-amide-carbonyls oriented toward th...

Heptamethine cyanine dyes are categorized as a class of near infrared fluorescent (NIRF) dyes which have been discovered to have tumor targeting and accumulation capability. This unique feature of NIRF dye makes it a promising candidate for imaging, targeted therapy and also as a drug delivery vehicle for various types of cancers. The favored uptake of dyes only in cancer cells is facilitated b...

Water-soluble derivatives of pyrrolopyrrole cyanines (PPCys) have been synthesized by a post-synthetic modification route. In highly polar media, these dyes are excellent NIR fluorophores. Labeling experiments show how these novel dyes are internalized into mammalian cells.

Despite the large interest in nuclear/optical multimodality imaging, the effect of radiation on the fluorescence of fluorophores remains largely unexplored. Herein, we report on the radiobleaching of cyanine fluorophores and describe conditions to provide robust radioprotection under practical (pre)clinical settings. We determined the radiosensitivity of several cyanine fluorescent compounds, i...

A reaction of methyl (4R,5R)-4,5-epoxy-2(E)-hexenoate 1 with N-benzylmethylamine gave a diastereomerically pure methyl (4R,5R)-4,5-epoxy-(3S)-N-benzylmethylamino hexanoate 6 and methyl (4S,5R)-4-N-benzyl-methylamino-5-hydroxy-2(E)-hexenoate 7. The former was chemoenzymatically converted to (-)-osmundalactone 11, which is an aglycone of osmundalin. On the other hand, the directly conjugated addi...