A Biopsychosocial Examination of ATOD Use among Middle and High School Students.

Objective: To examine Indiana middle and high school students' use of 17 licit and illicit substances using item response theory to produce theta scores to identify sociodemographics, psychological factors, and normative beliefs associated with life-time drug use.

Methods: Cross-sectional data from 1233 students were examined. Theta scores were calculated across 17 substances using 2PL item response theory modeling.

S-pixyl analogues as photocleavable protecting groups for nucleosides.

Several analogues of the 9-phenylthioxanthyl (S-pixyl) photocleavable protecting group have been synthesized, containing substituents on the 9-aryl ring and on the thioxanthyl backbone. Each analogue protected the 5'-hydroxy moiety of thymidine in good to excellent yield. The protected substrates were deprotected in 1:1 water:acetonitrile with irradiation at 300 nm, resulting in recovered thymidine in excellent yield, except for the nitro-substituted analogues which gave substantially lower yields.