A new derivatizing reagent, dansylaminomethylmaleic acid (DAM), was synthesized and utilized for the reversible fluorescence labeling of amino groups. The reagent DAM was dehydrated in the presence of (trimethylsilyl)ethoxyacetylene, a dehydrating agent, and the resulting anhydride reacted with amino groups, and could then be liberated under mild acidic conditions. With this reagent, benzylamine was derivatized as a model amino compound. The resultant fluorescent derivative, N-benzyl-2-dansylaminomethylmaleamic acid (BDAM), could be detected at 520 nm with fluorescence excitation at 340 nm. The fluorescence detection limit of BDAM (100 fmol, S/N=3) was smaller than that of intact benzylamine (200 pmol, S/N=10, absorbance at 254 nm). Under mild acidic conditions of pH 5.0, 82% of benzylamine was regenerated from BDAM within a day. With this reagent, insulin was successfully derivatized and 56% of insulin was regenerated.
The characteristics of linear motor with function of linear transformer for a future wireless light rail vehicle (LRV) are studied analytically by using the two types of numerical analyses. The dynamic characteristics in running condition are cleared. It is confirmed that the special motor has the satisfied thrust. The waveform of line current in the commercial source power on ground can be sinusoidal when the current of onboard winding is controlled sinusoidaL On this motor, the handling power of winding is in proportion to the pole pitch if the resistive loss of winding is neglected. As a merit, the full regenerating brake can be used at full speed.
For the identification of a peptidyl principle inducing sexual agglutination in the yeast, 2 supposed hexapeptides (1a, b) were synthesized by the conventional method. The 1a (H-Arg-Gly-Pro-Phe-Pro-Ile-OH) revealed complete identity with the natural peptide in TLC, MS and biological property on agglutination. The 1b showed the sexual agglutinability in the same degree as 1a, though distinct differences were observed in the chemical data. Both 1a and 1b had a strong bitter taste.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.