3-(3-aminopropoxy)-N-[(1R)-6-(6,7-dihydro-5H-pyrrolo[1,2-a]imidazol-2-yl)-2,3-dihydro-1H-inden-1-yl]-5-(hydroxymethyl)-4-methylbenzamide;(2S,4R)-1-[(2S)-2-[3-[2-[2-[2-[2-[3-[3-[5-[[(1R)-6-(6,7-dihydro-5H-pyrrolo[1,2-a]imidazol-2-yl)-2,3-dihydro-1H-inden-1-yl]carbamoyl]-3-(hydroxymethyl)-2-methylphenoxy]propylamino]-3-oxopropoxy]ethoxy]ethoxy]ethoxy]ethoxy]propanoylamino]-3,3-dimethylbutanoyl]-4-hydroxy-N-[[4-(4-methyl-1,3-thiazol-5-yl)phenyl]methyl]pyrrolidine-2-carboxamide;3-[2-[2-[2-[2-[(5S)-5-[(2S,4R)-4-hydroxy-2-[3-[4-(4-methyl-1,3-thiazol-5-yl)phenyl]propanoyl]pyrrolidine-1-carbonyl]-6,6-dimethyl-3-oxoheptoxy]ethoxy]ethoxy]ethoxy]ethoxy]propanoic acid

C128H172N14O27S2 — CID 167582317

About 3-(3-aminopropoxy)-N-[(1R)-6-(6,7-dihydro-5H-pyrrolo[1,2-a]imidazol-2-yl)-2,3-dihydro-1H-inden-1-yl]-5-(hydroxymethyl)-4-methylbenzamide;(2S,4R)-1-[(2S)-2-[3-[2-[2-[2-[2-[3-[3-[5-[[(1R)-6-(6,7-dihydro-5H-pyrrolo[1,2-a]imidazol-2-yl)-2,3-dihydro-1H-inden-1-yl]carbamoyl]-3-(hydroxymethyl)-2-methylphenoxy]propylamino]-3-oxopropoxy]ethoxy]ethoxy]ethoxy]ethoxy]propanoylamino]-3,3-dimethylbutanoyl]-4-hydroxy-N-[[4-(4-methyl-1,3-thiazol-5-yl)phenyl]methyl]pyrrolidine-2-carboxamide;3-[2-[2-[2-[2-[(5S)-5-[(2S,4R)-4-hydroxy-2-[3-[4-(4-methyl-1,3-thiazol-5-yl)phenyl]propanoyl]pyrrolidine-1-carbonyl]-6,6-dimethyl-3-oxoheptoxy]ethoxy]ethoxy]ethoxy]ethoxy]propanoic acid

3-(3-aminopropoxy)-N-[(1R)-6-(6,7-dihydro-5H-pyrrolo[1,2-a]imidazol-2-yl)-2,3-dihydro-1H-inden-1-yl]-5-(hydroxymethyl)-4-methylbenzamide;(2S,4R)-1-[(2S)-2-[3-[2-[2-[2-[2-[3-[3-[5-[[(1R)-6-(6,7-dihydro-5H-pyrrolo[1,2-a]imidazol-2-yl)-2,3-dihydro-1H-inden-1-yl]carbamoyl]-3-(hydroxymethyl)-2-methylphenoxy]propylamino]-3-oxopropoxy]ethoxy]ethoxy]ethoxy]ethoxy]propanoylamino]-3,3-dimethylbutanoyl]-4-hydroxy-N-[[4-(4-methyl-1,3-thiazol-5-yl)phenyl]methyl]pyrrolidine-2-carboxamide;3-[2-[2-[2-[2-[(5S)-5-[(2S,4R)-4-hydroxy-2-[3-[4-(4-methyl-1,3-thiazol-5-yl)phenyl]propanoyl]pyrrolidine-1-carbonyl]-6,6-dimethyl-3-oxoheptoxy]ethoxy]ethoxy]ethoxy]ethoxy]propanoic acid (PubChem CID 167582317) has the molecular formula C128H172N14O27S2 and a molecular weight of 2402.99 g/mol. Its IUPAC name is 3-(3-aminopropoxy)-N-[(1R)-6-(6,7-dihydro-5H-pyrrolo[1,2-a]imidazol-2-yl)-2,3-dihydro-1H-inden-1-yl]-5-(hydroxymethyl)-4-methylbenzamide;(2S,4R)-1-[(2S)-2-[3-[2-[2-[2-[2-[3-[3-[5-[[(1R)-6-(6,7-dihydro-5H-pyrrolo[1,2-a]imidazol-2-yl)-2,3-dihydro-1H-inden-1-yl]carbamoyl]-3-(hydroxymethyl)-2-methylphenoxy]propylamino]-3-oxopropoxy]ethoxy]ethoxy]ethoxy]ethoxy]propanoylamino]-3,3-dimethylbutanoyl]-4-hydroxy-N-[[4-(4-methyl-1,3-thiazol-5-yl)phenyl]methyl]pyrrolidine-2-carboxamide;3-[2-[2-[2-[2-[(5S)-5-[(2S,4R)-4-hydroxy-2-[3-[4-(4-methyl-1,3-thiazol-5-yl)phenyl]propanoyl]pyrrolidine-1-carbonyl]-6,6-dimethyl-3-oxoheptoxy]ethoxy]ethoxy]ethoxy]ethoxy]propanoic acid.

Molecular Properties

• Compound Name: 3-(3-aminopropoxy)-N-[(1R)-6-(6,7-dihydro-5H-pyrrolo[1,2-a]imidazol-2-yl)-2,3-dihydro-1H-inden-1-yl]-5-(hydroxymethyl)-4-methylbenzamide;(2S,4R)-1-[(2S)-2-[3-[2-[2-[2-[2-[3-[3-[5-[[(1R)-6-(6,7-dihydro-5H-pyrrolo[1,2-a]imidazol-2-yl)-2,3-dihydro-1H-inden-1-yl]carbamoyl]-3-(hydroxymethyl)-2-methylphenoxy]propylamino]-3-oxopropoxy]ethoxy]ethoxy]ethoxy]ethoxy]propanoylamino]-3,3-dimethylbutanoyl]-4-hydroxy-N-[[4-(4-methyl-1,3-thiazol-5-yl)phenyl]methyl]pyrrolidine-2-carboxamide;3-[2-[2-[2-[2-[(5S)-5-[(2S,4R)-4-hydroxy-2-[3-[4-(4-methyl-1,3-thiazol-5-yl)phenyl]propanoyl]pyrrolidine-1-carbonyl]-6,6-dimethyl-3-oxoheptoxy]ethoxy]ethoxy]ethoxy]ethoxy]propanoic acid
• PubChem CID: 167582317
• Molecular Formula: C128H172N14O27S2
• Molecular Weight: 2402.99 g/mol
• Exact Mass: 2401.20
• IUPAC Name: 3-(3-aminopropoxy)-N-[(1R)-6-(6,7-dihydro-5H-pyrrolo[1,2-a]imidazol-2-yl)-2,3-dihydro-1H-inden-1-yl]-5-(hydroxymethyl)-4-methylbenzamide;(2S,4R)-1-[(2S)-2-[3-[2-[2-[2-[2-[3-[3-[5-[[(1R)-6-(6,7-dihydro-5H-pyrrolo[1,2-a]imidazol-2-yl)-2,3-dihydro-1H-inden-1-yl]carbamoyl]-3-(hydroxymethyl)-2-methylphenoxy]propylamino]-3-oxopropoxy]ethoxy]ethoxy]ethoxy]ethoxy]propanoylamino]-3,3-dimethylbutanoyl]-4-hydroxy-N-[[4-(4-methyl-1,3-thiazol-5-yl)phenyl]methyl]pyrrolidine-2-carboxamide;3-[2-[2-[2-[2-[(5S)-5-[(2S,4R)-4-hydroxy-2-[3-[4-(4-methyl-1,3-thiazol-5-yl)phenyl]propanoyl]pyrrolidine-1-carbonyl]-6,6-dimethyl-3-oxoheptoxy]ethoxy]ethoxy]ethoxy]ethoxy]propanoic acid
• SMILES: Cc1c(CO)cc(C(=O)N[C@@H]2CCc3ccc(-c4cn5c(n4)CCC5)cc32)cc1OCCCN.Cc1ncsc1-c1ccc(CCC(=O)[C@@H]2C[C@@H](O)CN2C(=O)[C@@H](CC(=O)CCOCCOCCOCCOCCOCCC(=O)O)C(C)(C)C)cc1.Cc1ncsc1-c1ccc(CNC(=O)[C@@H]2C[C@@H](O)CN2C(=O)[C@@H](NC(=O)CCOCCOCCOCCOCCOCCC(=O)NCCCOc2cc(C(=O)N[C@@H]3CCc4ccc(-c5cn6c(n5)CCC6)cc43)cc(CO)c2C)C(C)(C)C)cc1
• InChI: InChI=1S/C63H84N8O13S.C38H56N2O11S.C27H32N4O3/c1-41-48(39-72)32-47(60(76)68-51-16-15-44-13-14-46(33-50(44)51)52-38-70-20-6-8-55(70)67-52)34-54(41)84-21-7-19-64-56(74)17-22-79-24-26-81-28-30-83-31-29-82-27-25-80-23-18-57(75)69-59(63(3,4)5)62(78)71-37-49(73)35-53(71)61(77)65-36-43-9-11-45(12-10-43)58-42(2)66-40-85-58;1-27-36(52-26-39-27)29-8-5-28(6-9-29)7-10-34(43)33-24-31(42)25-40(33)37(46)32(38(2,3)4)23-30(41)11-13-47-15-17-49-19-21-51-22-20-50-18-16-48-14-12-35(44)45;1-17-21(16-32)12-20(14-25(17)34-11-3-9-28)27(33)30-23-8-7-18-5-6-19(13-22(18)23)24-15-31-10-2-4-26(31)29-24/h9-14,32-34,38,40,49,51,53,59,72-73H,6-8,15-31,35-37,39H2,1-5H3,(H,64,74)(H,65,77)(H,68,76)(H,69,75);5-6,8-9,26,31-33,42H,7,10-25H2,1-4H3,(H,44,45);5-6,12-15,23,32H,2-4,7-11,16,28H2,1H3,(H,30,33)/t49-,51-,53+,59-;31-,32-,33+;23-/m111/s1
• InChIKey: HIKZQBSPKQBZMS-CXPSHKLMSA-N
• XLogP: 13.30
• TPSA: 536.68 Ų
• H-Bond Donors: 11
• H-Bond Acceptors: 35
• Rotatable Bonds: 67
• Heavy Atoms: 171
• Complexity: —

Lipinski Rule of Five

4 violations

Rule	Value
MW ≤ 500	2402.99
LogP ≤ 5	13.30
H-Bond Donors ≤ 5	11
H-Bond Acceptors ≤ 10	35

Computed Properties (RDKit)

• Structural Alerts: {'alert_name': 'Aliphatic_long_chain', 'substructure': 'N/A'}

Frequently Asked Questions

What is the IUPAC name of 3-(3-aminopropoxy)-N-[(1R)-6-(6,7-dihydro-5H-pyrrolo[1,2-a]imidazol-2-yl)-2,3-dihydro-1H-inden-1-yl]-5-(hydroxymethyl)-4-methylbenzamide;(2S,4R)-1-[(2S)-2-[3-[2-[2-[2-[2-[3-[3-[5-[[(1R)-6-(6,7-dihydro-5H-pyrrolo[1,2-a]imidazol-2-yl)-2,3-dihydro-1H-inden-1-yl]carbamoyl]-3-(hydroxymethyl)-2-methylphenoxy]propylamino]-3-oxopropoxy]ethoxy]ethoxy]ethoxy]ethoxy]propanoylamino]-3,3-dimethylbutanoyl]-4-hydroxy-N-[[4-(4-methyl-1,3-thiazol-5-yl)phenyl]methyl]pyrrolidine-2-carboxamide;3-[2-[2-[2-[2-[(5S)-5-[(2S,4R)-4-hydroxy-2-[3-[4-(4-methyl-1,3-thiazol-5-yl)phenyl]propanoyl]pyrrolidine-1-carbonyl]-6,6-dimethyl-3-oxoheptoxy]ethoxy]ethoxy]ethoxy]ethoxy]propanoic acid?

The IUPAC name of 3-(3-aminopropoxy)-N-[(1R)-6-(6,7-dihydro-5H-pyrrolo[1,2-a]imidazol-2-yl)-2,3-dihydro-1H-inden-1-yl]-5-(hydroxymethyl)-4-methylbenzamide;(2S,4R)-1-[(2S)-2-[3-[2-[2-[2-[2-[3-[3-[5-[[(1R)-6-(6,7-dihydro-5H-pyrrolo[1,2-a]imidazol-2-yl)-2,3-dihydro-1H-inden-1-yl]carbamoyl]-3-(hydroxymethyl)-2-methylphenoxy]propylamino]-3-oxopropoxy]ethoxy]ethoxy]ethoxy]ethoxy]propanoylamino]-3,3-dimethylbutanoyl]-4-hydroxy-N-[[4-(4-methyl-1,3-thiazol-5-yl)phenyl]methyl]pyrrolidine-2-carboxamide;3-[2-[2-[2-[2-[(5S)-5-[(2S,4R)-4-hydroxy-2-[3-[4-(4-methyl-1,3-thiazol-5-yl)phenyl]propanoyl]pyrrolidine-1-carbonyl]-6,6-dimethyl-3-oxoheptoxy]ethoxy]ethoxy]ethoxy]ethoxy]propanoic acid (CID 167582317) is 3-(3-aminopropoxy)-N-[(1R)-6-(6,7-dihydro-5H-pyrrolo[1,2-a]imidazol-2-yl)-2,3-dihydro-1H-inden-1-yl]-5-(hydroxymethyl)-4-methylbenzamide;(2S,4R)-1-[(2S)-2-[3-[2-[2-[2-[2-[3-[3-[5-[[(1R)-6-(6,7-dihydro-5H-pyrrolo[1,2-a]imidazol-2-yl)-2,3-dihydro-1H-inden-1-yl]carbamoyl]-3-(hydroxymethyl)-2-methylphenoxy]propylamino]-3-oxopropoxy]ethoxy]ethoxy]ethoxy]ethoxy]propanoylamino]-3,3-dimethylbutanoyl]-4-hydroxy-N-[[4-(4-methyl-1,3-thiazol-5-yl)phenyl]methyl]pyrrolidine-2-carboxamide;3-[2-[2-[2-[2-[(5S)-5-[(2S,4R)-4-hydroxy-2-[3-[4-(4-methyl-1,3-thiazol-5-yl)phenyl]propanoyl]pyrrolidine-1-carbonyl]-6,6-dimethyl-3-oxoheptoxy]ethoxy]ethoxy]ethoxy]ethoxy]propanoic acid.

What is the SMILES notation for 3-(3-aminopropoxy)-N-[(1R)-6-(6,7-dihydro-5H-pyrrolo[1,2-a]imidazol-2-yl)-2,3-dihydro-1H-inden-1-yl]-5-(hydroxymethyl)-4-methylbenzamide;(2S,4R)-1-[(2S)-2-[3-[2-[2-[2-[2-[3-[3-[5-[[(1R)-6-(6,7-dihydro-5H-pyrrolo[1,2-a]imidazol-2-yl)-2,3-dihydro-1H-inden-1-yl]carbamoyl]-3-(hydroxymethyl)-2-methylphenoxy]propylamino]-3-oxopropoxy]ethoxy]ethoxy]ethoxy]ethoxy]propanoylamino]-3,3-dimethylbutanoyl]-4-hydroxy-N-[[4-(4-methyl-1,3-thiazol-5-yl)phenyl]methyl]pyrrolidine-2-carboxamide;3-[2-[2-[2-[2-[(5S)-5-[(2S,4R)-4-hydroxy-2-[3-[4-(4-methyl-1,3-thiazol-5-yl)phenyl]propanoyl]pyrrolidine-1-carbonyl]-6,6-dimethyl-3-oxoheptoxy]ethoxy]ethoxy]ethoxy]ethoxy]propanoic acid?

The canonical SMILES for 3-(3-aminopropoxy)-N-[(1R)-6-(6,7-dihydro-5H-pyrrolo[1,2-a]imidazol-2-yl)-2,3-dihydro-1H-inden-1-yl]-5-(hydroxymethyl)-4-methylbenzamide;(2S,4R)-1-[(2S)-2-[3-[2-[2-[2-[2-[3-[3-[5-[[(1R)-6-(6,7-dihydro-5H-pyrrolo[1,2-a]imidazol-2-yl)-2,3-dihydro-1H-inden-1-yl]carbamoyl]-3-(hydroxymethyl)-2-methylphenoxy]propylamino]-3-oxopropoxy]ethoxy]ethoxy]ethoxy]ethoxy]propanoylamino]-3,3-dimethylbutanoyl]-4-hydroxy-N-[[4-(4-methyl-1,3-thiazol-5-yl)phenyl]methyl]pyrrolidine-2-carboxamide;3-[2-[2-[2-[2-[(5S)-5-[(2S,4R)-4-hydroxy-2-[3-[4-(4-methyl-1,3-thiazol-5-yl)phenyl]propanoyl]pyrrolidine-1-carbonyl]-6,6-dimethyl-3-oxoheptoxy]ethoxy]ethoxy]ethoxy]ethoxy]propanoic acid is Cc1c(CO)cc(C(=O)N[C@@H]2CCc3ccc(-c4cn5c(n4)CCC5)cc32)cc1OCCCN.Cc1ncsc1-c1ccc(CCC(=O)[C@@H]2C[C@@H](O)CN2C(=O)[C@@H](CC(=O)CCOCCOCCOCCOCCOCCC(=O)O)C(C)(C)C)cc1.Cc1ncsc1-c1ccc(CNC(=O)[C@@H]2C[C@@H](O)CN2C(=O)[C@@H](NC(=O)CCOCCOCCOCCOCCOCCC(=O)NCCCOc2cc(C(=O)N[C@@H]3CCc4ccc(-c5cn6c(n5)CCC6)cc43)cc(CO)c2C)C(C)(C)C)cc1.

What is the InChIKey of 3-(3-aminopropoxy)-N-[(1R)-6-(6,7-dihydro-5H-pyrrolo[1,2-a]imidazol-2-yl)-2,3-dihydro-1H-inden-1-yl]-5-(hydroxymethyl)-4-methylbenzamide;(2S,4R)-1-[(2S)-2-[3-[2-[2-[2-[2-[3-[3-[5-[[(1R)-6-(6,7-dihydro-5H-pyrrolo[1,2-a]imidazol-2-yl)-2,3-dihydro-1H-inden-1-yl]carbamoyl]-3-(hydroxymethyl)-2-methylphenoxy]propylamino]-3-oxopropoxy]ethoxy]ethoxy]ethoxy]ethoxy]propanoylamino]-3,3-dimethylbutanoyl]-4-hydroxy-N-[[4-(4-methyl-1,3-thiazol-5-yl)phenyl]methyl]pyrrolidine-2-carboxamide;3-[2-[2-[2-[2-[(5S)-5-[(2S,4R)-4-hydroxy-2-[3-[4-(4-methyl-1,3-thiazol-5-yl)phenyl]propanoyl]pyrrolidine-1-carbonyl]-6,6-dimethyl-3-oxoheptoxy]ethoxy]ethoxy]ethoxy]ethoxy]propanoic acid?

The InChIKey is HIKZQBSPKQBZMS-CXPSHKLMSA-N. The full InChI is InChI=1S/C63H84N8O13S.C38H56N2O11S.C27H32N4O3/c1-41-48(39-72)32-47(60(76)68-51-16-15-44-13-14-46(33-50(44)51)52-38-70-20-6-8-55(70)67-52)34-54(41)84-21-7-19-64-56(74)17-22-79-24-26-81-28-30-83-31-29-82-27-25-80-23-18-57(75)69-59(63(3,4)5)62(78)71-37-49(73)35-53(71)61(77)65-36-43-9-11-45(12-10-43)58-42(2)66-40-85-58;1-27-36(52-26-39-27)29-8-5-28(6-9-29)7-10-34(43)33-24-31(42)25-40(33)37(46)32(38(2,3)4)23-30(41)11-13-47-15-17-49-19-21-51-22-20-50-18-16-48-14-12-35(44)45;1-17-21(16-32)12-20(14-25(17)34-11-3-9-28)27(33)30-23-8-7-18-5-6-19(13-22(18)23)24-15-31-10-2-4-26(31)29-24/h9-14,32-34,38,40,49,51,53,59,72-73H,6-8,15-31,35-37,39H2,1-5H3,(H,64,74)(H,65,77)(H,68,76)(H,69,75);5-6,8-9,26,31-33,42H,7,10-25H2,1-4H3,(H,44,45);5-6,12-15,23,32H,2-4,7-11,16,28H2,1H3,(H,30,33)/t49-,51-,53+,59-;31-,32-,33+;23-/m111/s1.

What are the key properties of 3-(3-aminopropoxy)-N-[(1R)-6-(6,7-dihydro-5H-pyrrolo[1,2-a]imidazol-2-yl)-2,3-dihydro-1H-inden-1-yl]-5-(hydroxymethyl)-4-methylbenzamide;(2S,4R)-1-[(2S)-2-[3-[2-[2-[2-[2-[3-[3-[5-[[(1R)-6-(6,7-dihydro-5H-pyrrolo[1,2-a]imidazol-2-yl)-2,3-dihydro-1H-inden-1-yl]carbamoyl]-3-(hydroxymethyl)-2-methylphenoxy]propylamino]-3-oxopropoxy]ethoxy]ethoxy]ethoxy]ethoxy]propanoylamino]-3,3-dimethylbutanoyl]-4-hydroxy-N-[[4-(4-methyl-1,3-thiazol-5-yl)phenyl]methyl]pyrrolidine-2-carboxamide;3-[2-[2-[2-[2-[(5S)-5-[(2S,4R)-4-hydroxy-2-[3-[4-(4-methyl-1,3-thiazol-5-yl)phenyl]propanoyl]pyrrolidine-1-carbonyl]-6,6-dimethyl-3-oxoheptoxy]ethoxy]ethoxy]ethoxy]ethoxy]propanoic acid?

3-(3-aminopropoxy)-N-[(1R)-6-(6,7-dihydro-5H-pyrrolo[1,2-a]imidazol-2-yl)-2,3-dihydro-1H-inden-1-yl]-5-(hydroxymethyl)-4-methylbenzamide;(2S,4R)-1-[(2S)-2-[3-[2-[2-[2-[2-[3-[3-[5-[[(1R)-6-(6,7-dihydro-5H-pyrrolo[1,2-a]imidazol-2-yl)-2,3-dihydro-1H-inden-1-yl]carbamoyl]-3-(hydroxymethyl)-2-methylphenoxy]propylamino]-3-oxopropoxy]ethoxy]ethoxy]ethoxy]ethoxy]propanoylamino]-3,3-dimethylbutanoyl]-4-hydroxy-N-[[4-(4-methyl-1,3-thiazol-5-yl)phenyl]methyl]pyrrolidine-2-carboxamide;3-[2-[2-[2-[2-[(5S)-5-[(2S,4R)-4-hydroxy-2-[3-[4-(4-methyl-1,3-thiazol-5-yl)phenyl]propanoyl]pyrrolidine-1-carbonyl]-6,6-dimethyl-3-oxoheptoxy]ethoxy]ethoxy]ethoxy]ethoxy]propanoic acid has a molecular weight of 2402.99 g/mol, XLogP of 13.30, 67 rotatable bonds, 11 hydrogen bond donors, and 35 hydrogen bond acceptors.

Where does this data come from?

All data for 3-(3-aminopropoxy)-N-[(1R)-6-(6,7-dihydro-5H-pyrrolo[1,2-a]imidazol-2-yl)-2,3-dihydro-1H-inden-1-yl]-5-(hydroxymethyl)-4-methylbenzamide;(2S,4R)-1-[(2S)-2-[3-[2-[2-[2-[2-[3-[3-[5-[[(1R)-6-(6,7-dihydro-5H-pyrrolo[1,2-a]imidazol-2-yl)-2,3-dihydro-1H-inden-1-yl]carbamoyl]-3-(hydroxymethyl)-2-methylphenoxy]propylamino]-3-oxopropoxy]ethoxy]ethoxy]ethoxy]ethoxy]propanoylamino]-3,3-dimethylbutanoyl]-4-hydroxy-N-[[4-(4-methyl-1,3-thiazol-5-yl)phenyl]methyl]pyrrolidine-2-carboxamide;3-[2-[2-[2-[2-[(5S)-5-[(2S,4R)-4-hydroxy-2-[3-[4-(4-methyl-1,3-thiazol-5-yl)phenyl]propanoyl]pyrrolidine-1-carbonyl]-6,6-dimethyl-3-oxoheptoxy]ethoxy]ethoxy]ethoxy]ethoxy]propanoic acid is sourced from PubChem (CID 167582317), the world's largest open chemistry database maintained by the National Library of Medicine (NIH).