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Application of an almost traceless linker in the synthesis of 2-alkylthiobenzimidazole combinatorial libraries
R M Slade1, M A Phillips, J G Berger
1SIDDCO, Tucson, AZ 85747, USA. sladeboy@earthlink.net
Abstract:
Resin-bound triphenylphosphine was coupled to 4-fluoro-3-nitrobenzyl bromide, and 2-alkylthiobenzimidazoles were synthesized on resin in 4 steps using standard chemistries. Cleavage of the compounds from the resin was achieved with 10% NaOH in MeOH to leave a methyl group at the attachment point. A total of 47 amines and 40 electrophiles were evaluated, defining the scope of the reactions, culminating in the synthesis of an 80-member test library of high purity as determined by HPLC.
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