ISSN:
1434-193X
Keywords:
Sponge alkaloids
;
Protecting groups
;
Macrocycles
;
Chemistry
;
General Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
A general method was developed for the synthesis of a variety of symmetric and asymmetric macrocyclic bispyridines. 3-Hydroxyalkylpyridines 18-20 were prepared, converted to the corresponding iodides and protected on the pyridine nitrogen with a p-methoxybenzyl group to give the crystalline precursors 21, 22 and 23. Reaction with a second 3-hydroxyalkylpyridine gave the corresponding bis (3-alkylpyridinium) salts, which could easily be deprotected by refluxing in pyridine (24-29). Cyclization of the iodides in refluxing acetonitrile under high dilution conditions (1-2 mM) gave the desired macrocyles in overall yields between 65 and 74%. This efficient procedure resulted in the synthesis of the muscarinic receptor antagonists cyclostellettamines A-F (1-6) and some unnatural cyclophanes (12 and 31).
Type of Medium:
Electronic Resource
