New Sugar‐Based Permeant Analogs of D‐Myo‐Inositol 1,4,5‐Trisphosphate Mimicking the Effect of Vasopressin: Synthesis and Biologic Evaluation*

On the basis of the xylose‐inositol analogy, a series of permeant analogs of D‐myo‐inositol 1,4,5‐trisphosphate (InsP₃) have been synthesized by various esterifications of the phosphate groups. Their ability to cross the cell membrane has been tested on vasopressin cells. Very fast liberation of calcium occurs when active analogs are introduced in the extracellular medium on intact cells. Membrane crossing as well as hydrolysis of the phosphate is very rapid using acyloxymethyl esterification of all the phosphate groups. The free compounds behave in the cell like InsP₃. One of the analogs prepared this way behaves like vasopressin for rat hepatocyte cells expressing vasopressin receptor.