1	9J3	4-ethoxy-4-oxobutanoic acid	1.000
2	NF3	(~{z})-4-ethoxy-4-oxidanylidene-but-2-enoic acid	1.000
3	AW9	(2z)-4-methoxy-4-oxobut-2-enoic acid	0.900
4	HMB	(4s)-4-hydroxy-4-methoxybutanoic acid	0.900
5	MSU	Succinic acid monomethyl ester	0.900
6	UR9	(E)-4-methoxy-4-oxidanylidene-but-2-enoic acid	0.900
7	0AK	(2s)-2-amino-4-(2-chloroethoxy)-4-oxobutanoic acid	0.833
8	5F0	(3~{S})-3-azanyl-4-methoxy-4-oxidanylidene-butanoic acid	0.818
9	BKQ	Ethyl levulinate	0.818
10	FL6	(2s)-2-azanyl-4-methoxy-4-oxidanylidene-butanoic acid	0.818
11	ASB	Aspartic acid-4-carboxymethyl ester	0.769
12	A0A	(2s)-2-amino-4-(formyloxy)-4-oxobutanoic acid	0.750
13	AVG	2-amino-4-(2-amino-ethoxy)-butyric acid	0.750
14	AMB	L-2-amino-4-methoxy-cis-but-3-enoic acid	0.727
15	EAC	Ethyl 3-oxobutanoate	0.727
16	OKG	4-peroxy-4-oxobutanoic acid	0.727
17	ASL	Aspartic acid-4-carboxyethyl ester	0.714
18	CA1	Ethyl propionate	0.700
19	SSN	4-oxobutanoic acid	0.700