Table 3 Number of chemical structures generated by OMG and MOLGEN using as input only the elemental compositions of metabolites containing C, O, H, N, P and S elements

Glycine HMDB00123 C2H5NO2

N_3 84

0.118

1.405

97

0.452

4.660

N_5 162

0.120

0.741

Acetyl-HMDB00532 C4H7NO3

18,469

0.282

0.015

26,530

126.117

4.754

Phenylalanine HMDB00159 C9H11NO2

277,810,163

2227.796

0.008

* More than 277,810,163

* not available

* not available

Glutamic acid HMDB00148 C5H9NO4

440,821

2.945

0.007

685,392

12,348.456

18.017

Phosphoenolpyruvic acid HMDB00263 C3H5O6P

P_3 51,323

0.562

0.011

83,977

761.378

9.067

P_5 129,421

1.398

0.011

Creatinine HMDB00562 C4H7N3O

93,323

0.933

0.010

303,601

3,921.157

12.915

Guanidinoacetic acid HMDB00128 C3H7N3O2

45,626

0.585

0.013

124,808

1,962.532

15.724

Cytosine HMDB00630 C4H5N3O

108,769

1.149

0.011

491,299

3,952.098

8.044

Uric acid HMDB00289 C5H4N4O3

464,899,034

3488.097

0.008

* More than 464,899,034

* not available

* not available

Histamine HMDB00870 C5H9N3

46,125

0.631

0.014

134,278

3,566.544

26.561

D-Cysteine HMDB03417 C3H7NO2S

3,838

0.156

0.041

15,978

131.004

8.199

p-Cresol sulfate HMDB11635 C7H8O4S

S_6

5078.132

0.009

* More than 82,000,000

* not available

* not available

592,625,133