SYNTHESIS AND CHARACTERIZATION OF NEW THEBAINE DERIVATIVES: 2-(6,14-ENDO-ETHENOTETRAHYDROTHEBAINE-7 alpha-YL)-5-(N-ARYLAMINO)-1,3,4-THIADIAZOLES

We have synthesized a series of novel 2-(6,14-endo-ethenotetrahydrothebaine-7 alpha-yl)-5-N-arylamino-1,3,4-thiadiazoles (5a-n) as potential narcotic analgesics, which are analogs of morphine. The synthesized compounds exhibit rigid morphine structures, including a 6,14-endo-entheno bridge and a 5-N-arylamino-1,3,4-thiadiazol-2-yl group at C-7 position that adopted S-configuration. The structures and stereochemistry of the compounds were completely assigned using one-and two-dimensional NMR experiments (H-1 NMR, APT, COSY, NOESY, HMQC, and HMBC), FTIR, and high-resolution mass spectral (HRMS) data.