N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-(1,4-diazepan-1-yl)pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-[(3R)-3-methylpiperidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-[3-(trifluoromethyl)piperidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;[(2S)-2-[6-methyl-5-[(3S)-3-methylpyrrolidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidin-1-yl]-(2-methylphenyl)methanone;[(2S)-2-[6-methyl-5-[(3S)-3-methylpyrrolidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidin-1-yl]-(3-methylphenyl)methanone

C133H166Cl3F3N32O11S3 — CID 159343124

About N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-(1,4-diazepan-1-yl)pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-[(3R)-3-methylpiperidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-[3-(trifluoromethyl)piperidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;[(2S)-2-[6-methyl-5-[(3S)-3-methylpyrrolidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidin-1-yl]-(2-methylphenyl)methanone;[(2S)-2-[6-methyl-5-[(3S)-3-methylpyrrolidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidin-1-yl]-(3-methylphenyl)methanone

N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-(1,4-diazepan-1-yl)pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-[(3R)-3-methylpiperidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-[3-(trifluoromethyl)piperidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;[(2S)-2-[6-methyl-5-[(3S)-3-methylpyrrolidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidin-1-yl]-(2-methylphenyl)methanone;[(2S)-2-[6-methyl-5-[(3S)-3-methylpyrrolidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidin-1-yl]-(3-methylphenyl)methanone (PubChem CID 159343124) has the molecular formula C133H166Cl3F3N32O11S3 and a molecular weight of 2648.56 g/mol. Its IUPAC name is N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-(1,4-diazepan-1-yl)pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-[(3R)-3-methylpiperidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-[3-(trifluoromethyl)piperidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;[(2S)-2-[6-methyl-5-[(3S)-3-methylpyrrolidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidin-1-yl]-(2-methylphenyl)methanone;[(2S)-2-[6-methyl-5-[(3S)-3-methylpyrrolidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidin-1-yl]-(3-methylphenyl)methanone.

Molecular Properties

• Compound Name: N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-(1,4-diazepan-1-yl)pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-[(3R)-3-methylpiperidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-[3-(trifluoromethyl)piperidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;[(2S)-2-[6-methyl-5-[(3S)-3-methylpyrrolidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidin-1-yl]-(2-methylphenyl)methanone;[(2S)-2-[6-methyl-5-[(3S)-3-methylpyrrolidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidin-1-yl]-(3-methylphenyl)methanone
• PubChem CID: 159343124
• Molecular Formula: C133H166Cl3F3N32O11S3
• Molecular Weight: 2648.56 g/mol
• Exact Mass: 2645.16
• IUPAC Name: N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-(1,4-diazepan-1-yl)pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-[(3R)-3-methylpiperidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-[3-(trifluoromethyl)piperidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;[(2S)-2-[6-methyl-5-[(3S)-3-methylpyrrolidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidin-1-yl]-(2-methylphenyl)methanone;[(2S)-2-[6-methyl-5-[(3S)-3-methylpyrrolidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidin-1-yl]-(3-methylphenyl)methanone
• SMILES: CS(=O)(=O)Nc1ccc(Cl)cc1C(=O)N1CCCC[C@H]1c1cc2nc(N3CCC3)cc(N3CCCC(C(F)(F)F)C3)n2n1.CS(=O)(=O)Nc1ccc(Cl)cc1C(=O)N1CCCC[C@H]1c1cc2nc(N3CCC3)cc(N3CCCNCC3)n2n1.C[C@@H]1CCCN(c2cc(N3CCC3)nc3cc([C@@H]4CCCCN4C(=O)c4cc(Cl)ccc4NS(C)(=O)=O)nn23)C1.Cc1cccc(C(=O)N2CCCC[C@H]2c2cc3nc(N4CC[C@H](C)C4)c(C)cn3n2)c1.Cc1ccccc1C(=O)N1CCCC[C@H]1c1cc2nc(N3CC[C@H](C)C3)c(C)cn2n1
• InChI: InChI=1S/C28H33ClF3N7O3S.C28H36ClN7O3S.C27H35ClN8O3S.2C25H31N5O/c1-43(41,42)35-21-9-8-19(29)14-20(21)27(40)38-13-3-2-7-23(38)22-15-25-33-24(36-11-5-12-36)16-26(39(25)34-22)37-10-4-6-18(17-37)28(30,31)32;1-19-7-5-11-34(18-19)27-17-25(33-12-6-13-33)30-26-16-23(31-36(26)27)24-8-3-4-14-35(24)28(37)21-15-20(29)9-10-22(21)32-40(2,38)39;1-40(38,39)32-21-8-7-19(28)16-20(21)27(37)35-14-3-2-6-23(35)22-17-25-30-24(33-12-5-13-33)18-26(36(25)31-22)34-11-4-9-29-10-15-34;1-17-7-6-8-20(13-17)25(31)29-11-5-4-9-22(29)21-14-23-26-24(19(3)16-30(23)27-21)28-12-10-18(2)15-28;1-17-11-13-28(15-17)24-19(3)16-30-23(26-24)14-21(27-30)22-10-6-7-12-29(22)25(31)20-9-5-4-8-18(20)2/h8-9,14-16,18,23,35H,2-7,10-13,17H2,1H3;9-10,15-17,19,24,32H,3-8,11-14,18H2,1-2H3;7-8,16-18,23,29,32H,2-6,9-15H2,1H3;6-8,13-14,16,18,22H,4-5,9-12,15H2,1-3H3;4-5,8-9,14,16-17,22H,6-7,10-13,15H2,1-3H3/t18?,23-;19-,24+;23-;18-,22-;17-,22-/m01000/s1
• InChIKey: LGJOBZXOULYHEI-JUABGVBNSA-N
• XLogP: 21.93
• TPSA: 428.96 Ų
• H-Bond Donors: 4
• H-Bond Acceptors: 35
• Rotatable Bonds: 24
• Heavy Atoms: 185
• Complexity: —

Lipinski Rule of Five

3 violations

Rule	Value
MW ≤ 500	2648.56
LogP ≤ 5	21.93
H-Bond Donors ≤ 5	4
H-Bond Acceptors ≤ 10	35

Frequently Asked Questions

What is the IUPAC name of N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-(1,4-diazepan-1-yl)pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-[(3R)-3-methylpiperidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-[3-(trifluoromethyl)piperidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;[(2S)-2-[6-methyl-5-[(3S)-3-methylpyrrolidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidin-1-yl]-(2-methylphenyl)methanone;[(2S)-2-[6-methyl-5-[(3S)-3-methylpyrrolidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidin-1-yl]-(3-methylphenyl)methanone?

The IUPAC name of N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-(1,4-diazepan-1-yl)pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-[(3R)-3-methylpiperidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-[3-(trifluoromethyl)piperidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;[(2S)-2-[6-methyl-5-[(3S)-3-methylpyrrolidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidin-1-yl]-(2-methylphenyl)methanone;[(2S)-2-[6-methyl-5-[(3S)-3-methylpyrrolidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidin-1-yl]-(3-methylphenyl)methanone (CID 159343124) is N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-(1,4-diazepan-1-yl)pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-[(3R)-3-methylpiperidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-[3-(trifluoromethyl)piperidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;[(2S)-2-[6-methyl-5-[(3S)-3-methylpyrrolidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidin-1-yl]-(2-methylphenyl)methanone;[(2S)-2-[6-methyl-5-[(3S)-3-methylpyrrolidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidin-1-yl]-(3-methylphenyl)methanone.

What is the SMILES notation for N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-(1,4-diazepan-1-yl)pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-[(3R)-3-methylpiperidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-[3-(trifluoromethyl)piperidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;[(2S)-2-[6-methyl-5-[(3S)-3-methylpyrrolidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidin-1-yl]-(2-methylphenyl)methanone;[(2S)-2-[6-methyl-5-[(3S)-3-methylpyrrolidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidin-1-yl]-(3-methylphenyl)methanone?

The canonical SMILES for N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-(1,4-diazepan-1-yl)pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-[(3R)-3-methylpiperidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-[3-(trifluoromethyl)piperidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;[(2S)-2-[6-methyl-5-[(3S)-3-methylpyrrolidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidin-1-yl]-(2-methylphenyl)methanone;[(2S)-2-[6-methyl-5-[(3S)-3-methylpyrrolidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidin-1-yl]-(3-methylphenyl)methanone is CS(=O)(=O)Nc1ccc(Cl)cc1C(=O)N1CCCC[C@H]1c1cc2nc(N3CCC3)cc(N3CCCC(C(F)(F)F)C3)n2n1.CS(=O)(=O)Nc1ccc(Cl)cc1C(=O)N1CCCC[C@H]1c1cc2nc(N3CCC3)cc(N3CCCNCC3)n2n1.C[C@@H]1CCCN(c2cc(N3CCC3)nc3cc([C@@H]4CCCCN4C(=O)c4cc(Cl)ccc4NS(C)(=O)=O)nn23)C1.Cc1cccc(C(=O)N2CCCC[C@H]2c2cc3nc(N4CC[C@H](C)C4)c(C)cn3n2)c1.Cc1ccccc1C(=O)N1CCCC[C@H]1c1cc2nc(N3CC[C@H](C)C3)c(C)cn2n1.

What is the InChIKey of N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-(1,4-diazepan-1-yl)pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-[(3R)-3-methylpiperidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-[3-(trifluoromethyl)piperidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;[(2S)-2-[6-methyl-5-[(3S)-3-methylpyrrolidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidin-1-yl]-(2-methylphenyl)methanone;[(2S)-2-[6-methyl-5-[(3S)-3-methylpyrrolidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidin-1-yl]-(3-methylphenyl)methanone?

The InChIKey is LGJOBZXOULYHEI-JUABGVBNSA-N. The full InChI is InChI=1S/C28H33ClF3N7O3S.C28H36ClN7O3S.C27H35ClN8O3S.2C25H31N5O/c1-43(41,42)35-21-9-8-19(29)14-20(21)27(40)38-13-3-2-7-23(38)22-15-25-33-24(36-11-5-12-36)16-26(39(25)34-22)37-10-4-6-18(17-37)28(30,31)32;1-19-7-5-11-34(18-19)27-17-25(33-12-6-13-33)30-26-16-23(31-36(26)27)24-8-3-4-14-35(24)28(37)21-15-20(29)9-10-22(21)32-40(2,38)39;1-40(38,39)32-21-8-7-19(28)16-20(21)27(37)35-14-3-2-6-23(35)22-17-25-30-24(33-12-5-13-33)18-26(36(25)31-22)34-11-4-9-29-10-15-34;1-17-7-6-8-20(13-17)25(31)29-11-5-4-9-22(29)21-14-23-26-24(19(3)16-30(23)27-21)28-12-10-18(2)15-28;1-17-11-13-28(15-17)24-19(3)16-30-23(26-24)14-21(27-30)22-10-6-7-12-29(22)25(31)20-9-5-4-8-18(20)2/h8-9,14-16,18,23,35H,2-7,10-13,17H2,1H3;9-10,15-17,19,24,32H,3-8,11-14,18H2,1-2H3;7-8,16-18,23,29,32H,2-6,9-15H2,1H3;6-8,13-14,16,18,22H,4-5,9-12,15H2,1-3H3;4-5,8-9,14,16-17,22H,6-7,10-13,15H2,1-3H3/t18?,23-;19-,24+;23-;18-,22-;17-,22-/m01000/s1.

What are the key properties of N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-(1,4-diazepan-1-yl)pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-[(3R)-3-methylpiperidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-[3-(trifluoromethyl)piperidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;[(2S)-2-[6-methyl-5-[(3S)-3-methylpyrrolidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidin-1-yl]-(2-methylphenyl)methanone;[(2S)-2-[6-methyl-5-[(3S)-3-methylpyrrolidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidin-1-yl]-(3-methylphenyl)methanone?

N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-(1,4-diazepan-1-yl)pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-[(3R)-3-methylpiperidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-[3-(trifluoromethyl)piperidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;[(2S)-2-[6-methyl-5-[(3S)-3-methylpyrrolidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidin-1-yl]-(2-methylphenyl)methanone;[(2S)-2-[6-methyl-5-[(3S)-3-methylpyrrolidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidin-1-yl]-(3-methylphenyl)methanone has a molecular weight of 2648.56 g/mol, XLogP of 21.93, 24 rotatable bonds, 4 hydrogen bond donors, and 35 hydrogen bond acceptors.

Where does this data come from?

All data for N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-(1,4-diazepan-1-yl)pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-[(3R)-3-methylpiperidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;N-[2-[(2S)-2-[5-(azetidin-1-yl)-7-[3-(trifluoromethyl)piperidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidine-1-carbonyl]-4-chlorophenyl]methanesulfonamide;[(2S)-2-[6-methyl-5-[(3S)-3-methylpyrrolidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidin-1-yl]-(2-methylphenyl)methanone;[(2S)-2-[6-methyl-5-[(3S)-3-methylpyrrolidin-1-yl]pyrazolo[1,5-a]pyrimidin-2-yl]piperidin-1-yl]-(3-methylphenyl)methanone is sourced from PubChem (CID 159343124), the world's largest open chemistry database maintained by the National Library of Medicine (NIH).