1	9MG	9-methylguanine	1.000
2	NDM	7,9-dimethylguanine	0.923
3	GUN	Guanine	0.917
4	8IG	8-iodo-guanine	0.846
5	ANG	8-aminoguanine	0.846
6	B55	2-amino-8-sulfanyl-1,9-dihydro-6h-purin-6-one	0.846
7	BRG	8-bromoguanine	0.846
8	MY6	2-amino-7-methyl-1,7-dihydro-6h-purin-6-one	0.846
9	OXG	8-oxoguanine	0.846
10	W5M	9-methyl-9h-purine-2,6-diamine	0.846
11	2BP	9h-purin-2-amine	0.833
12	HPA	Hypoxanthine	0.833
13	B60	2-amino-8-methyl-7,8-dihydropteridin-4(3h)-one	0.786
14	MUA	9-methyl uric acid	0.786
15	UAN	9-methyl-2-(methylamino)-1h-purin-6-one	0.786
16	2ON	2-sulfanyl-1,9-dihydro-6h-purin-6-one	0.769
17	6AP	9h-purine-2,6-diamine	0.769
18	6GU	6-chloroguanine	0.769
19	7DG	7-deazaguanine	0.769
20	8G8	2-chloranyl-9-methyl-purine	0.769
21	9DG	9-deazaguanine	0.769
22	ADZ	9-methyl-9h-purin-6-amine	0.769
23	AZG	5-amino-1h-[1,2,3]triazolo[4,5-D]pyrimidin-7-ol	0.769
24	BOA	2-bromo-6-hydroxy-purine	0.769
25	DX4	2-amino-1,9-dihydro-6h-purine-6-thione	0.769
26	HH5	6-iodanyl-7~{H}-purin-2-amine	0.769
27	QY8	2-amino-3h,4h,7h-pyrrolo[2,3-D]pyrimidin-4-one	0.769
28	XAN	Xanthine	0.769
29	AC2	9-hyroxyethoxymethylguanine	0.750
30	29H	2-aminopyrimido[4,5-D]pyrimidin-4(3h)-one	0.714
31	2EC	9-ethyl-9h-purin-6-ylamine	0.714
32	39A	6-amino-3,9-dimethyl-9h-purin-3-ium	0.714
33	5JL	2,8-dithioxo-1,2,3,7,8,9-hexahydro-6h-purin-6-one	0.714
34	5JQ	2-thioxo-2,3,7,9-tetrahydro-1h-purine-6,8-dione	0.714
35	6GO	6-O-methylguanine	0.714
36	8HX	8-hydroxy-3,9-dihydro-1h-purine-2,6-dione	0.714
37	8TX	8-thioxo-3,7,8,9-tetrahydro-1h-purine-2,6-dione	0.714
38	FDB	2-amino-5-methyl-3h-pyrrolo[2,3-D]pyrimidin-4(7h)-one	0.714
39	MOG	5-amino-2-methyl-6h-oxazolo[5,4-D]pyrimidin-7-one	0.714
40	OYK	~{N},9-dimethylpurin-6-amine	0.714
41	PE0	Pterine	0.714
42	QBK	5-azanyl-[1,3]thiazolo[5,4-D]pyrimidine-2,7-dione	0.714
43	T0A	5-deazatetrahydropterin	0.714
44	URC	Uric acid	0.714
45	8Y7	[(2-amino-9-methyl-6-oxo-6,9-dihydro-1h-purin-8-yl)sulfanyl]acetic acid	0.706
46	AGD	3-(2-amino-6-oxo-1,6-dihydro-9h-purin-9-yl)-D-alanine	0.706