STRUCTURAL STUDIES ON THE ANTIMUSCARINIC AGENTS SPIRO-DAMP AND HYDROXY-DAMP, AND COMPARISON WITH RELATED-COMPOUNDS

Compound (I), 3-diphenyl-1,4-dioxa-8-azoniaspiro[4.5]decan-2-one iodid e, spiro-DAMP, has the ester moiety enclosed in a rigid dioxolane ring , giving rise to a spiro piperidine derivative. Compound (II), roxy-2, 2-diphenylacetoxy)-1,1-dimethylpiperidinium iodide, hydroxy-DAMP, show s the ester substituent in an equatorial position with respect to the piperidine ring, compared to an axial position in (I). Consequently, t he topology of both polar and hydrophobic groups in the two derivative s is quite different. Comparisons are made with related antimuscarinic compounds, such as 4-DAMP, azaprophen and (-)-atropine.