1	28Y	3h-imidazo[2,1-B]purin-4(5h)-one	1.000
2	A1IEC	N,2,3-etheno-2-aminopurine	0.923
3	HPA	Hypoxanthine	0.769
4	2ON	2-sulfanyl-1,9-dihydro-6h-purin-6-one	0.714
5	BOA	2-bromo-6-hydroxy-purine	0.714
6	GUN	Guanine	0.714
7	K7L	(4s)-imidazo[1,2-a]pyrimidine-5,7-diol	0.714
8	XAN	Xanthine	0.714