Subject(s)
Peptidomimetics , Protease Inhibitors , Severe acute respiratory syndrome-related coronavirus/enzymology , Viral Proteins/antagonists & inhibitors , Amino Acids , Coronavirus 3C Proteases , Cysteine Endopeptidases , Drug Design , Inhibitory Concentration 50 , Molecular Structure , Oligopeptides/chemical synthesis , Peptidomimetics/chemical synthesis , Protease Inhibitors/chemical synthesis , Substrate SpecificitySubject(s)
Cysteine Endopeptidases/chemistry , Peptidomimetics , Protease Inhibitors , Severe acute respiratory syndrome-related coronavirus/enzymology , Viral Proteins/chemistry , Amino Acids , Coronavirus 3C Proteases , Drug Design , Inhibitory Concentration 50 , Molecular Structure , Oligopeptides/chemical synthesis , Peptidomimetics/chemical synthesis , Protease Inhibitors/chemical synthesis , Severe acute respiratory syndrome-related coronavirus/classification , Substrate Specificity , Viral Proteins/antagonists & inhibitorsABSTRACT
The Suzuki coupling of optically active (S)-binaphthyl bromide 10 with (S)-binaphthyl boronic acid 11 produced a diastereomeric mixture of tetrahydroxyquaternaphthyls 4. The coupling products 4as well as their derivatives 5-7 can be considered as members of the family of 1,1'-binaphthyl-3,3'-diols. The C-1-C'-1 axis of all these compounds was found to have an unusually high rotational barrier. Generally, the barrier is higher for derivatives having more bulky substituents at the 3 and 3' positions.
ABSTRACT
A series of poly(beta-alanine) dendrimers 1-4 with Boc-carbamate as the surface functionality, beta-alanine as the dendritic branch, 3,5-diaminobenzoic acid as the branching agent, and 1,2diaminoethane as the interior core has been synthesized by a solution-phase peptide-coupling method. The structural identities and purities of the products have been fully characterized by spectroscopic and chromatographic methods. 1H NMR studies on the dendrimers indicated that the Boc-carbamate surface groups exist as a mixture of syn and anti rotamers in solution, and that the dendrimers adopt an open structure in polar solvents; this allows the free interaction of the interior core functionality with solvent molecules. Due to the cooperative effect of a large number of carbamate and amide groups, the dendrimers exhibit an unusually strong binding ability towards protic solvents and behave as H-bond sponges. As a result, the H/D exchange rates of the N-H protons are significantly enhanced in such dendritic structures, as compared to those of nondendritic carbamates and amides. These dendritic peptide dendrimers also exhibit a strong tendency to form nanoscopic aggregates in nonpolar or polar aprotic solvents through intermolecular H-bond interactions.