Total Synthesis of (+)-Pochonin D and (+)-Monocillin II via Chemo- and Regioselective Intramolecular Nitrile Oxide Cycloaddition

Asymmetric total syntheses of (+)-pochonin D (1) and (+)-monocillin II (2), Hsp90 inhibitors with potent anticancer activity, have been accomplished where the macrolactone 3 was constructed through a chemo- and regioselective intramolecular nitrile oxide cycloaddition of diene 4.

Additions of Azomethine Ylides to Fullerene C(60) Assisted by a Removable Anchor

The addition of nitrile oxides to [60]fullerene, leading to isoxazolinofullerenes, can be reversed using reducing agents such as Mo(CO)(6) or DIBALH. Thus, this reaction can be used, in principle, for protection/deprotection of [60]fullerene or for solubilization purposes. The tether-controlled tandem addition of nitrile oxides and azomethine ylides provides mainly cis-1 patterns. The determination of the structure of bisadducts was obtained by NMR spectroscopy with the help of HMQC, HMBC, and NOEDS techniques. The isoxazoline moiety could be removed using Mo(CO)(6) leaving a fulleropyrrolidine derivative.