The highly efficient and expedient route for the syntheses of 2-aroyl benzofurans has been developed via the cascade [2+2] followed by a [4+1] annulation on arynes. The overall transformation proceeded through the formation of ortho-quinone methide by the insertion of transient aryne into N, N-dimethylformamide and subsequent trapping with sulfur ylide. Moreover, this transformation has a broad range of substrate scope with a high functional-group tolerance. This new reaction was successfully utilized in the synthesis of the potent CYP19 aromatase inhibitor and late-stage functionalization on the bioactive complex estrone.

The formal total synthesis of pentacyclic core alkaloid, (±)-cephalotaxine is achieved in nine steps from known 2-allylpyrrolidine-2-carboxaldehyde using aryne insertion reaction as a key step in 10% overall yield. The developed novel strategy enabled easy access to cephalotaxine congeners.

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The enantiomeric non-natural cyclic amino acids (3R,4R)-1amino-3-fluoro-4-(fluoro-18 F)cyclopentane-1-carboxylic acid and (3S,4S)-1amino-3-fluoro-4-(fluoro-18 F)cyclopentane-1-carboxylic acid ([ 18 F]5) have been prepared as a racemic mixture in 1.3% decay corrected radiochemical yield and in greater than 99% radiochemical purity. [ 18 F]5 is transported primarily via system L with some transport occurring via system ASC, as assessed in rat 9L gliosarcoma, human U87 ΔEGFR glioblastoma, and human DU145 androgen-independent prostate carcinoma tumor cells. In rats bearing intracranial 9L gliosarcoma, [ 18 F]5 gave tumor to contralateral brain tissue ratios of up to 2.8. Biodistribution studies in healthy rats demonstrated that bladder accumulation is delayed until 10 min postinjection.

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