PubMed HealthSearch

PubMed · 6864476

Stability constants for complex formation between alpha-cyclodextrin and some amines.

Abstract

Complex formation of alpha-cyclodextrin with 15 amines (including seven 4-substituted anilines) was studied by the potentiometric method, supplemented by direct UV spectrophotometry and a competitive indicator spectrophotometric method. The data were analyzed in terms of 1:1 and 1:2 complexes (amine-cyclodextrin ratios) and the stability constants K11a, K12a, K11b, and K12b were evaluated; the subscripts indicate the stoichiometry and conjugate acid-base form. For all amines K11b was greater than K11a and K12a was 0. On the basis of the relationship of complex stability to amine structure, it was concluded that the primary binding site in anilines is the 4-substituent.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

A B Wong, S F Lin, K A Connors. 1983. Stability constants for complex formation between alpha-cyclodextrin and some amines.. https://doi.org/10.1002/jps.2600720417

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

Site specific labelling of sugar residues in oligoribonucleotides: reactions of aliphatic isocyanates with 2' amino groups.

Considerable effort has been directed towards studying the structure and function of nucleic acids and several approaches rely on the attachment of reporter groups or reactive functional groups to nucleic acids. We report here the selective modification of 2-amino groups in oligoribonucleotides, through their reaction with aliphatic isocyanates, to give the corresponding 2'-urea derivatives in >95% yield. Furthermore, such modification with (2-isocyanato)ethyl 2-pyridyl disulfide enables subsequent coupling to other thiols (such as those contained in peptides and proteins) or to thiol-reactive electrophiles. A modified decamer was not significantly destabilized by the 2'-urea group, compared with a 2'-amino group, as demonstrated by a mere 1.3 degrees C drop in the melting temperature of the duplex.

Amines

Ion chromatography of amylamine and tert.-butylamine in pharmaceuticals.

Ion chromatographic (IC) methods have been developed for the assay of amylamine in BMS-181 866-02 and tert.-butylamine (TBA) in BMS-188 494-04. BMS-181 866-02 is the penultimate intermediate in the synthesis of a novel thromboxane antagonist, BMS-180 291-02, which is undergoing clinical trials. Amylamine may be present as a trace impurity in BMS-181 866-02. BMS-188 494-04 is the TBA salt of the prodrug ester of BMS-187 745, a novel oral hypocholesterolemic agent. Chromatographic separations were accomplished under isocratic conditions using a Dionex CS-14 column with conductivity detection. The methods differ only in the composition of the methanesulfonic acid-acetonitrile mobile phase. The detection limit and minimum quantifiable levels for amylamine were 0.01% and 0.02%, respectively. The method was linear over the range studied (1-12.5 micrograms/ml, n = 7, r = 0.9993). The method for TBA was linear from 5 to 30% (w/w) (50-300 micrograms/ml, n = 8, r = 0.9993) of working sample concentration (1 mg/ml BMS-188 494-04). The precision and accuracy of the methods are presented.

Amines

Aminodiol HIV protease inhibitors. Synthesis and structure-activity relationships of P1/P1' compounds: correlation between lipophilicity and cytotoxicity.

A series of novel aminodiol inhibitors of HIV protease based on the lead compound 1 with structural modifications at P1' were synthesized in order to reduce the cytotoxicity of 1. We have observed a high degree of correlation between the lipophilicity and cytotoxicity of this series of inhibitors. It was found that appropriate substitution at the para position of the P1' phenyl group of 1 resulted in the identification of equipotent (both against the enzyme and in cell culture) compounds (10l, 10m, 10n, and 15c) which possess significantly decreased cytotoxicity.

Amines