Concise syntheses and some biological activities ofdl-2,5-di-O-methyl-chiro-inositol,dl-1,4-di-O-methyl-scyllo-inositol, anddl-1,6-dibromo-1,6-dideoxy-2,5-di-O-methyl-chiro-inositol

The regio- and stereospecific synthesis ofO-methyl-chiro-inositols andO-methyl-scyllo-inositol was achieved, starting fromp-benzoquinone. After preparing dimethoxy conduritol-B as a key compound, regiospecific bromination of the alkene moiety of dimethoxy conduritol-B and acid-catalyzed ring opening of dimethoxydiacetate conduritol-B epoxide with Ac2O afforded the desired newchiro-inositol derivatives andscyllo-inositol derivative, respectively. Spectroscopic methods were employed for the characterization of all synthesized compounds. The novel inositols (11-17) had effective inhibition profiles against human carbonic anhydrase isoenzymes I and II (hCA I and II) and acetylcholinesterase (AChE). The novel inositols11-17were found to be effective inhibitors against AChE, hCA I, and hCA II enzymes.K(i)values were calculated in the range of 87.59 +/- 7.011 to 237.95 +/- 17.75 mu M for hCA I, 65.08 +/- 12.39 to 538.98 +/- 61.26 mu M for hCA II, and 193.28 +/- 43.13 to 765.08 +/- 209.77 mu M for AChE, respectively. Also, due to the inhibitory effects of the novel inositols11-17against the tested enzymes, these novel inositols are potential drug candidates to treat some diseases such as glaucoma, epilepsy, leukemia, and Alzheimer's disease.