1-[1-tert-butyl-3-(2,2-dimethyl-3-oxopiperazine-1-carbonyl)pyrazol-4-yl]-3-[4-methyl-3-[5-(morpholin-4-ylmethyl)-2-pyridinyl]phenyl]urea;1-[5-tert-butyl-2-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)furan-3-yl]-3-[4-methyl-3-[5-(morpholin-4-ylmethyl)-2-pyridinyl]phenyl]urea;5-[5-[[5-tert-butyl-2-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-3-yl]carbamoylamino]-2-methylphenyl]-N-ethylpyridine-2-carboxamide;5-[5-[[5-tert-butyl-3-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-2-yl]carbamoylamino]-2-methylphenyl]pyridine-2-carboxamide;1-[5-tert-butyl-3-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-2-yl]-3-[3-[6-(2-hydroxypropan-2-yl)-3-pyridinyl]-4-methylphenyl]urea

C160H203N31O21S3 — CID 158365012

About 1-[1-tert-butyl-3-(2,2-dimethyl-3-oxopiperazine-1-carbonyl)pyrazol-4-yl]-3-[4-methyl-3-[5-(morpholin-4-ylmethyl)-2-pyridinyl]phenyl]urea;1-[5-tert-butyl-2-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)furan-3-yl]-3-[4-methyl-3-[5-(morpholin-4-ylmethyl)-2-pyridinyl]phenyl]urea;5-[5-[[5-tert-butyl-2-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-3-yl]carbamoylamino]-2-methylphenyl]-N-ethylpyridine-2-carboxamide;5-[5-[[5-tert-butyl-3-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-2-yl]carbamoylamino]-2-methylphenyl]pyridine-2-carboxamide;1-[5-tert-butyl-3-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-2-yl]-3-[3-[6-(2-hydroxypropan-2-yl)-3-pyridinyl]-4-methylphenyl]urea

1-[1-tert-butyl-3-(2,2-dimethyl-3-oxopiperazine-1-carbonyl)pyrazol-4-yl]-3-[4-methyl-3-[5-(morpholin-4-ylmethyl)-2-pyridinyl]phenyl]urea;1-[5-tert-butyl-2-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)furan-3-yl]-3-[4-methyl-3-[5-(morpholin-4-ylmethyl)-2-pyridinyl]phenyl]urea;5-[5-[[5-tert-butyl-2-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-3-yl]carbamoylamino]-2-methylphenyl]-N-ethylpyridine-2-carboxamide;5-[5-[[5-tert-butyl-3-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-2-yl]carbamoylamino]-2-methylphenyl]pyridine-2-carboxamide;1-[5-tert-butyl-3-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-2-yl]-3-[3-[6-(2-hydroxypropan-2-yl)-3-pyridinyl]-4-methylphenyl]urea (PubChem CID 158365012) has the molecular formula C160H203N31O21S3 and a molecular weight of 2992.78 g/mol. Its IUPAC name is 1-[1-tert-butyl-3-(2,2-dimethyl-3-oxopiperazine-1-carbonyl)pyrazol-4-yl]-3-[4-methyl-3-[5-(morpholin-4-ylmethyl)-2-pyridinyl]phenyl]urea;1-[5-tert-butyl-2-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)furan-3-yl]-3-[4-methyl-3-[5-(morpholin-4-ylmethyl)-2-pyridinyl]phenyl]urea;5-[5-[[5-tert-butyl-2-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-3-yl]carbamoylamino]-2-methylphenyl]-N-ethylpyridine-2-carboxamide;5-[5-[[5-tert-butyl-3-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-2-yl]carbamoylamino]-2-methylphenyl]pyridine-2-carboxamide;1-[5-tert-butyl-3-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-2-yl]-3-[3-[6-(2-hydroxypropan-2-yl)-3-pyridinyl]-4-methylphenyl]urea.

Molecular Properties

• Compound Name: 1-[1-tert-butyl-3-(2,2-dimethyl-3-oxopiperazine-1-carbonyl)pyrazol-4-yl]-3-[4-methyl-3-[5-(morpholin-4-ylmethyl)-2-pyridinyl]phenyl]urea;1-[5-tert-butyl-2-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)furan-3-yl]-3-[4-methyl-3-[5-(morpholin-4-ylmethyl)-2-pyridinyl]phenyl]urea;5-[5-[[5-tert-butyl-2-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-3-yl]carbamoylamino]-2-methylphenyl]-N-ethylpyridine-2-carboxamide;5-[5-[[5-tert-butyl-3-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-2-yl]carbamoylamino]-2-methylphenyl]pyridine-2-carboxamide;1-[5-tert-butyl-3-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-2-yl]-3-[3-[6-(2-hydroxypropan-2-yl)-3-pyridinyl]-4-methylphenyl]urea
• PubChem CID: 158365012
• Molecular Formula: C160H203N31O21S3
• Molecular Weight: 2992.78 g/mol
• Exact Mass: 2990.49
• IUPAC Name: 1-[1-tert-butyl-3-(2,2-dimethyl-3-oxopiperazine-1-carbonyl)pyrazol-4-yl]-3-[4-methyl-3-[5-(morpholin-4-ylmethyl)-2-pyridinyl]phenyl]urea;1-[5-tert-butyl-2-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)furan-3-yl]-3-[4-methyl-3-[5-(morpholin-4-ylmethyl)-2-pyridinyl]phenyl]urea;5-[5-[[5-tert-butyl-2-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-3-yl]carbamoylamino]-2-methylphenyl]-N-ethylpyridine-2-carboxamide;5-[5-[[5-tert-butyl-3-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-2-yl]carbamoylamino]-2-methylphenyl]pyridine-2-carboxamide;1-[5-tert-butyl-3-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-2-yl]-3-[3-[6-(2-hydroxypropan-2-yl)-3-pyridinyl]-4-methylphenyl]urea
• SMILES: CCNC(=O)c1ccc(-c2cc(NC(=O)Nc3cc(C(C)(C)C)sc3C(=O)N3CCN(C)C(=O)C3(C)C)ccc2C)cn1.Cc1ccc(NC(=O)Nc2cc(C(C)(C)C)oc2C(=O)N2CCN(C)C(=O)C2(C)C)cc1-c1ccc(CN2CCOCC2)cn1.Cc1ccc(NC(=O)Nc2cn(C(C)(C)C)nc2C(=O)N2CCNC(=O)C2(C)C)cc1-c1ccc(CN2CCOCC2)cn1.Cc1ccc(NC(=O)Nc2sc(C(C)(C)C)cc2C(=O)N2CCN(C)C(=O)C2(C)C)cc1-c1ccc(C(C)(C)O)nc1.Cc1ccc(NC(=O)Nc2sc(C(C)(C)C)cc2C(=O)N2CCN(C)C(=O)C2(C)C)cc1-c1ccc(C(N)=O)nc1
• InChI: InChI=1S/C34H44N6O5.C32H42N8O4.C32H40N6O4S.C32H41N5O4S.C30H36N6O4S/c1-22-8-10-24(18-25(22)26-11-9-23(20-35-26)21-39-14-16-44-17-15-39)36-32(43)37-27-19-28(33(2,3)4)45-29(27)30(41)40-13-12-38(7)31(42)34(40,5)6;1-21-7-9-23(17-24(21)25-10-8-22(18-34-25)19-38-13-15-44-16-14-38)35-30(43)36-26-20-40(31(2,3)4)37-27(26)28(41)39-12-11-33-29(42)32(39,5)6;1-9-33-27(39)23-13-11-20(18-34-23)22-16-21(12-10-19(22)2)35-30(42)36-24-17-25(31(3,4)5)43-26(24)28(40)38-15-14-37(8)29(41)32(38,6)7;1-19-10-12-21(16-22(19)20-11-13-24(33-18-20)32(7,8)41)34-29(40)35-26-23(17-25(42-26)30(2,3)4)27(38)37-15-14-36(9)28(39)31(37,5)6;1-17-8-10-19(14-20(17)18-9-11-22(24(31)37)32-16-18)33-28(40)34-25-21(15-23(41-25)29(2,3)4)26(38)36-13-12-35(7)27(39)30(36,5)6/h8-11,18-20H,12-17,21H2,1-7H3,(H2,36,37,43);7-10,17-18,20H,11-16,19H2,1-6H3,(H,33,42)(H2,35,36,43);10-13,16-18H,9,14-15H2,1-8H3,(H,33,39)(H2,35,36,42);10-13,16-18,41H,14-15H2,1-9H3,(H2,34,35,40);8-11,14-16H,12-13H2,1-7H3,(H2,31,37)(H2,33,34,40)
• InChIKey: GTXSJWMACDRUHF-UHFFFAOYSA-N
• XLogP: 25.29
• TPSA: 630.31 Ų
• H-Bond Donors: 14
• H-Bond Acceptors: 33
• Rotatable Bonds: 28
• Heavy Atoms: 215
• Complexity: —

Lipinski Rule of Five

4 violations

Rule	Value
MW ≤ 500	2992.78
LogP ≤ 5	25.29
H-Bond Donors ≤ 5	14
H-Bond Acceptors ≤ 10	33

Frequently Asked Questions

What is the IUPAC name of 1-[1-tert-butyl-3-(2,2-dimethyl-3-oxopiperazine-1-carbonyl)pyrazol-4-yl]-3-[4-methyl-3-[5-(morpholin-4-ylmethyl)-2-pyridinyl]phenyl]urea;1-[5-tert-butyl-2-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)furan-3-yl]-3-[4-methyl-3-[5-(morpholin-4-ylmethyl)-2-pyridinyl]phenyl]urea;5-[5-[[5-tert-butyl-2-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-3-yl]carbamoylamino]-2-methylphenyl]-N-ethylpyridine-2-carboxamide;5-[5-[[5-tert-butyl-3-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-2-yl]carbamoylamino]-2-methylphenyl]pyridine-2-carboxamide;1-[5-tert-butyl-3-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-2-yl]-3-[3-[6-(2-hydroxypropan-2-yl)-3-pyridinyl]-4-methylphenyl]urea?

The IUPAC name of 1-[1-tert-butyl-3-(2,2-dimethyl-3-oxopiperazine-1-carbonyl)pyrazol-4-yl]-3-[4-methyl-3-[5-(morpholin-4-ylmethyl)-2-pyridinyl]phenyl]urea;1-[5-tert-butyl-2-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)furan-3-yl]-3-[4-methyl-3-[5-(morpholin-4-ylmethyl)-2-pyridinyl]phenyl]urea;5-[5-[[5-tert-butyl-2-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-3-yl]carbamoylamino]-2-methylphenyl]-N-ethylpyridine-2-carboxamide;5-[5-[[5-tert-butyl-3-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-2-yl]carbamoylamino]-2-methylphenyl]pyridine-2-carboxamide;1-[5-tert-butyl-3-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-2-yl]-3-[3-[6-(2-hydroxypropan-2-yl)-3-pyridinyl]-4-methylphenyl]urea (CID 158365012) is 1-[1-tert-butyl-3-(2,2-dimethyl-3-oxopiperazine-1-carbonyl)pyrazol-4-yl]-3-[4-methyl-3-[5-(morpholin-4-ylmethyl)-2-pyridinyl]phenyl]urea;1-[5-tert-butyl-2-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)furan-3-yl]-3-[4-methyl-3-[5-(morpholin-4-ylmethyl)-2-pyridinyl]phenyl]urea;5-[5-[[5-tert-butyl-2-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-3-yl]carbamoylamino]-2-methylphenyl]-N-ethylpyridine-2-carboxamide;5-[5-[[5-tert-butyl-3-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-2-yl]carbamoylamino]-2-methylphenyl]pyridine-2-carboxamide;1-[5-tert-butyl-3-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-2-yl]-3-[3-[6-(2-hydroxypropan-2-yl)-3-pyridinyl]-4-methylphenyl]urea.

What is the SMILES notation for 1-[1-tert-butyl-3-(2,2-dimethyl-3-oxopiperazine-1-carbonyl)pyrazol-4-yl]-3-[4-methyl-3-[5-(morpholin-4-ylmethyl)-2-pyridinyl]phenyl]urea;1-[5-tert-butyl-2-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)furan-3-yl]-3-[4-methyl-3-[5-(morpholin-4-ylmethyl)-2-pyridinyl]phenyl]urea;5-[5-[[5-tert-butyl-2-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-3-yl]carbamoylamino]-2-methylphenyl]-N-ethylpyridine-2-carboxamide;5-[5-[[5-tert-butyl-3-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-2-yl]carbamoylamino]-2-methylphenyl]pyridine-2-carboxamide;1-[5-tert-butyl-3-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-2-yl]-3-[3-[6-(2-hydroxypropan-2-yl)-3-pyridinyl]-4-methylphenyl]urea?

The canonical SMILES for 1-[1-tert-butyl-3-(2,2-dimethyl-3-oxopiperazine-1-carbonyl)pyrazol-4-yl]-3-[4-methyl-3-[5-(morpholin-4-ylmethyl)-2-pyridinyl]phenyl]urea;1-[5-tert-butyl-2-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)furan-3-yl]-3-[4-methyl-3-[5-(morpholin-4-ylmethyl)-2-pyridinyl]phenyl]urea;5-[5-[[5-tert-butyl-2-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-3-yl]carbamoylamino]-2-methylphenyl]-N-ethylpyridine-2-carboxamide;5-[5-[[5-tert-butyl-3-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-2-yl]carbamoylamino]-2-methylphenyl]pyridine-2-carboxamide;1-[5-tert-butyl-3-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-2-yl]-3-[3-[6-(2-hydroxypropan-2-yl)-3-pyridinyl]-4-methylphenyl]urea is CCNC(=O)c1ccc(-c2cc(NC(=O)Nc3cc(C(C)(C)C)sc3C(=O)N3CCN(C)C(=O)C3(C)C)ccc2C)cn1.Cc1ccc(NC(=O)Nc2cc(C(C)(C)C)oc2C(=O)N2CCN(C)C(=O)C2(C)C)cc1-c1ccc(CN2CCOCC2)cn1.Cc1ccc(NC(=O)Nc2cn(C(C)(C)C)nc2C(=O)N2CCNC(=O)C2(C)C)cc1-c1ccc(CN2CCOCC2)cn1.Cc1ccc(NC(=O)Nc2sc(C(C)(C)C)cc2C(=O)N2CCN(C)C(=O)C2(C)C)cc1-c1ccc(C(C)(C)O)nc1.Cc1ccc(NC(=O)Nc2sc(C(C)(C)C)cc2C(=O)N2CCN(C)C(=O)C2(C)C)cc1-c1ccc(C(N)=O)nc1.

What is the InChIKey of 1-[1-tert-butyl-3-(2,2-dimethyl-3-oxopiperazine-1-carbonyl)pyrazol-4-yl]-3-[4-methyl-3-[5-(morpholin-4-ylmethyl)-2-pyridinyl]phenyl]urea;1-[5-tert-butyl-2-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)furan-3-yl]-3-[4-methyl-3-[5-(morpholin-4-ylmethyl)-2-pyridinyl]phenyl]urea;5-[5-[[5-tert-butyl-2-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-3-yl]carbamoylamino]-2-methylphenyl]-N-ethylpyridine-2-carboxamide;5-[5-[[5-tert-butyl-3-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-2-yl]carbamoylamino]-2-methylphenyl]pyridine-2-carboxamide;1-[5-tert-butyl-3-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-2-yl]-3-[3-[6-(2-hydroxypropan-2-yl)-3-pyridinyl]-4-methylphenyl]urea?

The InChIKey is GTXSJWMACDRUHF-UHFFFAOYSA-N. The full InChI is InChI=1S/C34H44N6O5.C32H42N8O4.C32H40N6O4S.C32H41N5O4S.C30H36N6O4S/c1-22-8-10-24(18-25(22)26-11-9-23(20-35-26)21-39-14-16-44-17-15-39)36-32(43)37-27-19-28(33(2,3)4)45-29(27)30(41)40-13-12-38(7)31(42)34(40,5)6;1-21-7-9-23(17-24(21)25-10-8-22(18-34-25)19-38-13-15-44-16-14-38)35-30(43)36-26-20-40(31(2,3)4)37-27(26)28(41)39-12-11-33-29(42)32(39,5)6;1-9-33-27(39)23-13-11-20(18-34-23)22-16-21(12-10-19(22)2)35-30(42)36-24-17-25(31(3,4)5)43-26(24)28(40)38-15-14-37(8)29(41)32(38,6)7;1-19-10-12-21(16-22(19)20-11-13-24(33-18-20)32(7,8)41)34-29(40)35-26-23(17-25(42-26)30(2,3)4)27(38)37-15-14-36(9)28(39)31(37,5)6;1-17-8-10-19(14-20(17)18-9-11-22(24(31)37)32-16-18)33-28(40)34-25-21(15-23(41-25)29(2,3)4)26(38)36-13-12-35(7)27(39)30(36,5)6/h8-11,18-20H,12-17,21H2,1-7H3,(H2,36,37,43);7-10,17-18,20H,11-16,19H2,1-6H3,(H,33,42)(H2,35,36,43);10-13,16-18H,9,14-15H2,1-8H3,(H,33,39)(H2,35,36,42);10-13,16-18,41H,14-15H2,1-9H3,(H2,34,35,40);8-11,14-16H,12-13H2,1-7H3,(H2,31,37)(H2,33,34,40).

What are the key properties of 1-[1-tert-butyl-3-(2,2-dimethyl-3-oxopiperazine-1-carbonyl)pyrazol-4-yl]-3-[4-methyl-3-[5-(morpholin-4-ylmethyl)-2-pyridinyl]phenyl]urea;1-[5-tert-butyl-2-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)furan-3-yl]-3-[4-methyl-3-[5-(morpholin-4-ylmethyl)-2-pyridinyl]phenyl]urea;5-[5-[[5-tert-butyl-2-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-3-yl]carbamoylamino]-2-methylphenyl]-N-ethylpyridine-2-carboxamide;5-[5-[[5-tert-butyl-3-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-2-yl]carbamoylamino]-2-methylphenyl]pyridine-2-carboxamide;1-[5-tert-butyl-3-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-2-yl]-3-[3-[6-(2-hydroxypropan-2-yl)-3-pyridinyl]-4-methylphenyl]urea?

1-[1-tert-butyl-3-(2,2-dimethyl-3-oxopiperazine-1-carbonyl)pyrazol-4-yl]-3-[4-methyl-3-[5-(morpholin-4-ylmethyl)-2-pyridinyl]phenyl]urea;1-[5-tert-butyl-2-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)furan-3-yl]-3-[4-methyl-3-[5-(morpholin-4-ylmethyl)-2-pyridinyl]phenyl]urea;5-[5-[[5-tert-butyl-2-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-3-yl]carbamoylamino]-2-methylphenyl]-N-ethylpyridine-2-carboxamide;5-[5-[[5-tert-butyl-3-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-2-yl]carbamoylamino]-2-methylphenyl]pyridine-2-carboxamide;1-[5-tert-butyl-3-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-2-yl]-3-[3-[6-(2-hydroxypropan-2-yl)-3-pyridinyl]-4-methylphenyl]urea has a molecular weight of 2992.78 g/mol, XLogP of 25.29, 28 rotatable bonds, 14 hydrogen bond donors, and 33 hydrogen bond acceptors.

Where does this data come from?

All data for 1-[1-tert-butyl-3-(2,2-dimethyl-3-oxopiperazine-1-carbonyl)pyrazol-4-yl]-3-[4-methyl-3-[5-(morpholin-4-ylmethyl)-2-pyridinyl]phenyl]urea;1-[5-tert-butyl-2-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)furan-3-yl]-3-[4-methyl-3-[5-(morpholin-4-ylmethyl)-2-pyridinyl]phenyl]urea;5-[5-[[5-tert-butyl-2-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-3-yl]carbamoylamino]-2-methylphenyl]-N-ethylpyridine-2-carboxamide;5-[5-[[5-tert-butyl-3-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-2-yl]carbamoylamino]-2-methylphenyl]pyridine-2-carboxamide;1-[5-tert-butyl-3-(2,2,4-trimethyl-3-oxopiperazine-1-carbonyl)thiophen-2-yl]-3-[3-[6-(2-hydroxypropan-2-yl)-3-pyridinyl]-4-methylphenyl]urea is sourced from PubChem (CID 158365012), the world's largest open chemistry database maintained by the National Library of Medicine (NIH).