Scalable Synthesis of Biologically Relevant Spirocyclic Pyrrolidines.

Synthetic approaches toward multigram preparation of spirocyclic α,α-disubstituted pyrrolidines from readily available starting materials are discussed. It was shown that although a number of synthetic methodologies have been known to date, many of the title compounds remain hardly accessible. The most appropriate literature method (which relied on reaction of imines and allyl magnesium halide, followed by bromocyclization) was identified and optimized.

Integral-equation method for interpreting laser-sounding data on atmospheric gas components using differential absorption.

Data on laser sounding of an atmospheric humidity field are interpreted by using the differential-absorption method. A regularizing algorithm for restoring the accuracy of the water-vapor profile by resolving the errors of optical measurements and fluctuations of the aerosol backscattering coefficient is suggested. The efficiency of the inversion method is illustrated, using a numerical experiment and examples of restitution of the humidity profiles based on data of laser sounding up to 8-km altitudes.