Designing combinatorial libraries for efficient screening.

Based on literature structures, we proposed a pharmacophore for NOP receptor ligands and used it as a guide for the design of a focused piperidine library and an optimization library. Potent NOP receptor agonists and antagonists were obtained from these libraries as well as a few potent, mu selective agonists.

Combinatorial Chemistry Techniques↗

PubMed2003

Synthesis of iduronic acid building blocks for the modular assembly of glycosaminoglycans.

The modular synthesis of glycosaminoglycans requires straightforward methods for the production of large quantities of protected uronic acid building blocks. In particular, the preparation of fully differentiated iduronic acids has proven particularly challenging. An efficient route to methyl 3-O-benzyl-1,2-O-isopropylidene-alpha-l-idopyranosiduronate 6 from diacetone glucose in nine steps and 36% overall yield is described. Idopyranosiduronate 6 is useful as a glycosyl acceptor and as an intermediate that may be further elaborated into iduronic acid trichloroacetimidate glycosyl donors for the assembly of glycosaminoglycan structures as illustrated here.

Combinatorial Chemistry Techniques↗

PubMed2003

Facile determination of the protecting group location of Nim-protected histidine derivatives by 1H-15N heteronuclear correlation NMR.

The positioning of the imidazole protecting group of several histidine derivatives was determined by means of (1)H-(15)N heteronuclear multiple-bond correlation NMR experiments. The cross-peak originated from the three-bond correlation between the histidine side-chain H(beta) and the imidazole N(pi) was used for the identification of the N(pi) signal in the (15)N spectrum. Therefore, based on the fact that the signal of the substituted imidazole nitrogen appears always at lower chemical shift (delta) than the unsubstituted one, the position of the blocking group could easily be inferred. The obtained data confirmed previous findings that were accomplished with other less generally applicable spectroscopic or crystallographic techniques.

Combinatorial Chemistry Techniques↗