150D:
reference: Guanine-1,N6-ethenoadenine base pairs in the crystal structure of d(CGCGAATT(epsilon dA)GCG)., Leonard GA, McAuley-Hecht KE, Gibson NJ, Brown T, Watson WP, Hunter WN, Biochemistry 1994 Apr 26;33(16):4755-61. PMID: 8161534

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