A diazirine's central carbon is sp-hybridized, facilitating conjugation to dye molecules.

Diazirines are versatile carbene precursors that are extensively used in biological target identification experiments. However, their photo-activation wavelength ( 365 nm) precludes their use in living organisms. Here we show that a reconceptualization of the diazirine hybridization state leads to conjugation of the diazirine motif to longer-wavelength chromophores.

Biomimetic Organocatalytic Approach to 4-Arylquinolizidine Alkaloids and Application in the Synthesis of (-)-Lasubine II and (+)-Subcosine II.

An enantioselective, biomimetic organocatalytic synthesis of 4-arylquinolizidin-2-ones, key intermediates in the synthesis of several Lythraceae alkaloids, was developed. The methodology features -proline-mediated Mannich/aza-Michael reactions of readily available arylideneacetones and Δ-piperideine. The total syntheses of (-)-lasubine II and (+)-subcosine II as well as the formal syntheses of structurally related Lythraceae alkaloids were achieved.