PROCESS FOR THE SCALABLE SYNTHESIS OF 1, 3, 4, 9-TETRAHYDROPYRANO[3, 4-B]-INDOLE DERIVATIVES.

摘要

The invention is directed to a process of synthesizing compouds of formula (VI), wherein R1, R9, R3 , R 4 and Y are as set forth in the specification, and said method is useful for large scale synthesis thereof. The invention is also directed to useful intermediates for synthesizing the compounds of formula (VI) and processes of preparing said intermediates.