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(A) Structural comparison of 2,4-difluorotoluene with thymine (B) Structures of thymidine analogs containing different halogens that vary in size (C) Comparison of mixed, nucleobase-modified base pairs including adenine: 2,4-difluorotoluene, 4-methylbenzimidazole:difluorotoluene, and 9-methylimidazo [ (Kool, 2002; Kool and Sintim, 2006)-b]pyridine: 2,4-difluorotoluene.
