(7R,10S,13S)-7-acetyl-13-[(4-fluorophenyl)sulfonylmethyl]-10-(2-methylpropyl)-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-triene-9,12-dione;(7R,10S,13R)-7-acetyl-13-[2-oxo-2-(1H-pyrrol-2-yl)ethyl]-10-propan-2-yl-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-triene-9,12-dione;benzyl 2-[(7R,10S,13R)-7-acetyl-9,12-dioxo-10-propan-2-yl-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-trien-13-yl]acetate;benzyl 2-[(9R,12S,15R)-9-acetyl-11,14-dioxo-12-propan-2-yl-2-oxa-7-thia-13-azabicyclo[15.2.2]henicosa-1(19),17,20-trien-15-yl]acetate;benzyl 2-[(8R,11S,14R)-8-acetyl-11-(2-methylpropyl)-10,13-dioxo-2-oxa-12-azabicyclo[14.2.2]icosa-1(18),16,19-trien-14-yl]acetate

C154H197FN6O29S2 — CID 158789759

About (7R,10S,13S)-7-acetyl-13-[(4-fluorophenyl)sulfonylmethyl]-10-(2-methylpropyl)-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-triene-9,12-dione;(7R,10S,13R)-7-acetyl-13-[2-oxo-2-(1H-pyrrol-2-yl)ethyl]-10-propan-2-yl-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-triene-9,12-dione;benzyl 2-[(7R,10S,13R)-7-acetyl-9,12-dioxo-10-propan-2-yl-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-trien-13-yl]acetate;benzyl 2-[(9R,12S,15R)-9-acetyl-11,14-dioxo-12-propan-2-yl-2-oxa-7-thia-13-azabicyclo[15.2.2]henicosa-1(19),17,20-trien-15-yl]acetate;benzyl 2-[(8R,11S,14R)-8-acetyl-11-(2-methylpropyl)-10,13-dioxo-2-oxa-12-azabicyclo[14.2.2]icosa-1(18),16,19-trien-14-yl]acetate

(7R,10S,13S)-7-acetyl-13-[(4-fluorophenyl)sulfonylmethyl]-10-(2-methylpropyl)-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-triene-9,12-dione;(7R,10S,13R)-7-acetyl-13-[2-oxo-2-(1H-pyrrol-2-yl)ethyl]-10-propan-2-yl-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-triene-9,12-dione;benzyl 2-[(7R,10S,13R)-7-acetyl-9,12-dioxo-10-propan-2-yl-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-trien-13-yl]acetate;benzyl 2-[(9R,12S,15R)-9-acetyl-11,14-dioxo-12-propan-2-yl-2-oxa-7-thia-13-azabicyclo[15.2.2]henicosa-1(19),17,20-trien-15-yl]acetate;benzyl 2-[(8R,11S,14R)-8-acetyl-11-(2-methylpropyl)-10,13-dioxo-2-oxa-12-azabicyclo[14.2.2]icosa-1(18),16,19-trien-14-yl]acetate (PubChem CID 158789759) has the molecular formula C154H197FN6O29S2 and a molecular weight of 2679.41 g/mol. Its IUPAC name is (7R,10S,13S)-7-acetyl-13-[(4-fluorophenyl)sulfonylmethyl]-10-(2-methylpropyl)-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-triene-9,12-dione;(7R,10S,13R)-7-acetyl-13-[2-oxo-2-(1H-pyrrol-2-yl)ethyl]-10-propan-2-yl-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-triene-9,12-dione;benzyl 2-[(7R,10S,13R)-7-acetyl-9,12-dioxo-10-propan-2-yl-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-trien-13-yl]acetate;benzyl 2-[(9R,12S,15R)-9-acetyl-11,14-dioxo-12-propan-2-yl-2-oxa-7-thia-13-azabicyclo[15.2.2]henicosa-1(19),17,20-trien-15-yl]acetate;benzyl 2-[(8R,11S,14R)-8-acetyl-11-(2-methylpropyl)-10,13-dioxo-2-oxa-12-azabicyclo[14.2.2]icosa-1(18),16,19-trien-14-yl]acetate.

Molecular Properties

• Compound Name: (7R,10S,13S)-7-acetyl-13-[(4-fluorophenyl)sulfonylmethyl]-10-(2-methylpropyl)-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-triene-9,12-dione;(7R,10S,13R)-7-acetyl-13-[2-oxo-2-(1H-pyrrol-2-yl)ethyl]-10-propan-2-yl-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-triene-9,12-dione;benzyl 2-[(7R,10S,13R)-7-acetyl-9,12-dioxo-10-propan-2-yl-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-trien-13-yl]acetate;benzyl 2-[(9R,12S,15R)-9-acetyl-11,14-dioxo-12-propan-2-yl-2-oxa-7-thia-13-azabicyclo[15.2.2]henicosa-1(19),17,20-trien-15-yl]acetate;benzyl 2-[(8R,11S,14R)-8-acetyl-11-(2-methylpropyl)-10,13-dioxo-2-oxa-12-azabicyclo[14.2.2]icosa-1(18),16,19-trien-14-yl]acetate
• PubChem CID: 158789759
• Molecular Formula: C154H197FN6O29S2
• Molecular Weight: 2679.41 g/mol
• Exact Mass: 2677.36
• IUPAC Name: (7R,10S,13S)-7-acetyl-13-[(4-fluorophenyl)sulfonylmethyl]-10-(2-methylpropyl)-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-triene-9,12-dione;(7R,10S,13R)-7-acetyl-13-[2-oxo-2-(1H-pyrrol-2-yl)ethyl]-10-propan-2-yl-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-triene-9,12-dione;benzyl 2-[(7R,10S,13R)-7-acetyl-9,12-dioxo-10-propan-2-yl-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-trien-13-yl]acetate;benzyl 2-[(9R,12S,15R)-9-acetyl-11,14-dioxo-12-propan-2-yl-2-oxa-7-thia-13-azabicyclo[15.2.2]henicosa-1(19),17,20-trien-15-yl]acetate;benzyl 2-[(8R,11S,14R)-8-acetyl-11-(2-methylpropyl)-10,13-dioxo-2-oxa-12-azabicyclo[14.2.2]icosa-1(18),16,19-trien-14-yl]acetate
• SMILES: CC(=O)[C@@H]1CCCCCOc2ccc(cc2)C[C@H](CC(=O)OCc2ccccc2)C(=O)N[C@@H](CC(C)C)C(=O)C1.CC(=O)[C@@H]1CCCCOc2ccc(cc2)C[C@H](CC(=O)OCc2ccccc2)C(=O)N[C@@H](C(C)C)C(=O)C1.CC(=O)[C@@H]1CCCCOc2ccc(cc2)C[C@H](CC(=O)c2ccc[nH]2)C(=O)N[C@@H](C(C)C)C(=O)C1.CC(=O)[C@@H]1CCCCOc2ccc(cc2)C[C@H](CS(=O)(=O)c2ccc(F)cc2)C(=O)N[C@@H](CC(C)C)C(=O)C1.CC(=O)[C@@H]1CSCCCCOc2ccc(cc2)C[C@H](CC(=O)OCc2ccccc2)C(=O)N[C@@H](C(C)C)C(=O)C1
• InChI: InChI=1S/C33H43NO6.C32H41NO6S.C31H39NO6.C30H38FNO6S.C28H36N2O5/c1-23(2)18-30-31(36)20-27(24(3)35)12-8-5-9-17-39-29-15-13-25(14-16-29)19-28(33(38)34-30)21-32(37)40-22-26-10-6-4-7-11-26;1-22(2)31-29(35)18-27(23(3)34)21-40-16-8-7-15-38-28-13-11-24(12-14-28)17-26(32(37)33-31)19-30(36)39-20-25-9-5-4-6-10-25;1-21(2)30-28(34)18-25(22(3)33)11-7-8-16-37-27-14-12-23(13-15-27)17-26(31(36)32-30)19-29(35)38-20-24-9-5-4-6-10-24;1-20(2)16-28-29(34)18-23(21(3)33)6-4-5-15-38-26-11-7-22(8-12-26)17-24(30(35)32-28)19-39(36,37)27-13-9-25(31)10-14-27;1-18(2)27-26(33)16-21(19(3)31)7-4-5-14-35-23-11-9-20(10-12-23)15-22(28(34)30-27)17-25(32)24-8-6-13-29-24/h4,6-7,10-11,13-16,23,27-28,30H,5,8-9,12,17-22H2,1-3H3,(H,34,38);4-6,9-14,22,26-27,31H,7-8,15-21H2,1-3H3,(H,33,37);4-6,9-10,12-15,21,25-26,30H,7-8,11,16-20H2,1-3H3,(H,32,36);7-14,20,23-24,28H,4-6,15-19H2,1-3H3,(H,32,35);6,8-13,18,21-22,27,29H,4-5,7,14-17H2,1-3H3,(H,30,34)/t27-,28-,30+;26-,27+,31+;25-,26-,30+;23-,24-,28+;21-,22-,27+/m11111/s1
• InChIKey: ISCXFFCFXLAMNO-GNPBQLKZSA-N
• XLogP: 24.69
• TPSA: 508.25 Ų
• H-Bond Donors: 6
• H-Bond Acceptors: 30
• Rotatable Bonds: 30
• Heavy Atoms: 192
• Complexity: —

Lipinski Rule of Five

4 violations

Rule	Value
MW ≤ 500	2679.41
LogP ≤ 5	24.69
H-Bond Donors ≤ 5	6
H-Bond Acceptors ≤ 10	30

Computed Properties (RDKit)

• Structural Alerts: {'alert_name': '>_2_ester_groups', 'substructure': 'N/A'}

Frequently Asked Questions

What is the IUPAC name of (7R,10S,13S)-7-acetyl-13-[(4-fluorophenyl)sulfonylmethyl]-10-(2-methylpropyl)-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-triene-9,12-dione;(7R,10S,13R)-7-acetyl-13-[2-oxo-2-(1H-pyrrol-2-yl)ethyl]-10-propan-2-yl-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-triene-9,12-dione;benzyl 2-[(7R,10S,13R)-7-acetyl-9,12-dioxo-10-propan-2-yl-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-trien-13-yl]acetate;benzyl 2-[(9R,12S,15R)-9-acetyl-11,14-dioxo-12-propan-2-yl-2-oxa-7-thia-13-azabicyclo[15.2.2]henicosa-1(19),17,20-trien-15-yl]acetate;benzyl 2-[(8R,11S,14R)-8-acetyl-11-(2-methylpropyl)-10,13-dioxo-2-oxa-12-azabicyclo[14.2.2]icosa-1(18),16,19-trien-14-yl]acetate?

The IUPAC name of (7R,10S,13S)-7-acetyl-13-[(4-fluorophenyl)sulfonylmethyl]-10-(2-methylpropyl)-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-triene-9,12-dione;(7R,10S,13R)-7-acetyl-13-[2-oxo-2-(1H-pyrrol-2-yl)ethyl]-10-propan-2-yl-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-triene-9,12-dione;benzyl 2-[(7R,10S,13R)-7-acetyl-9,12-dioxo-10-propan-2-yl-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-trien-13-yl]acetate;benzyl 2-[(9R,12S,15R)-9-acetyl-11,14-dioxo-12-propan-2-yl-2-oxa-7-thia-13-azabicyclo[15.2.2]henicosa-1(19),17,20-trien-15-yl]acetate;benzyl 2-[(8R,11S,14R)-8-acetyl-11-(2-methylpropyl)-10,13-dioxo-2-oxa-12-azabicyclo[14.2.2]icosa-1(18),16,19-trien-14-yl]acetate (CID 158789759) is (7R,10S,13S)-7-acetyl-13-[(4-fluorophenyl)sulfonylmethyl]-10-(2-methylpropyl)-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-triene-9,12-dione;(7R,10S,13R)-7-acetyl-13-[2-oxo-2-(1H-pyrrol-2-yl)ethyl]-10-propan-2-yl-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-triene-9,12-dione;benzyl 2-[(7R,10S,13R)-7-acetyl-9,12-dioxo-10-propan-2-yl-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-trien-13-yl]acetate;benzyl 2-[(9R,12S,15R)-9-acetyl-11,14-dioxo-12-propan-2-yl-2-oxa-7-thia-13-azabicyclo[15.2.2]henicosa-1(19),17,20-trien-15-yl]acetate;benzyl 2-[(8R,11S,14R)-8-acetyl-11-(2-methylpropyl)-10,13-dioxo-2-oxa-12-azabicyclo[14.2.2]icosa-1(18),16,19-trien-14-yl]acetate.

What is the SMILES notation for (7R,10S,13S)-7-acetyl-13-[(4-fluorophenyl)sulfonylmethyl]-10-(2-methylpropyl)-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-triene-9,12-dione;(7R,10S,13R)-7-acetyl-13-[2-oxo-2-(1H-pyrrol-2-yl)ethyl]-10-propan-2-yl-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-triene-9,12-dione;benzyl 2-[(7R,10S,13R)-7-acetyl-9,12-dioxo-10-propan-2-yl-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-trien-13-yl]acetate;benzyl 2-[(9R,12S,15R)-9-acetyl-11,14-dioxo-12-propan-2-yl-2-oxa-7-thia-13-azabicyclo[15.2.2]henicosa-1(19),17,20-trien-15-yl]acetate;benzyl 2-[(8R,11S,14R)-8-acetyl-11-(2-methylpropyl)-10,13-dioxo-2-oxa-12-azabicyclo[14.2.2]icosa-1(18),16,19-trien-14-yl]acetate?

The canonical SMILES for (7R,10S,13S)-7-acetyl-13-[(4-fluorophenyl)sulfonylmethyl]-10-(2-methylpropyl)-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-triene-9,12-dione;(7R,10S,13R)-7-acetyl-13-[2-oxo-2-(1H-pyrrol-2-yl)ethyl]-10-propan-2-yl-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-triene-9,12-dione;benzyl 2-[(7R,10S,13R)-7-acetyl-9,12-dioxo-10-propan-2-yl-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-trien-13-yl]acetate;benzyl 2-[(9R,12S,15R)-9-acetyl-11,14-dioxo-12-propan-2-yl-2-oxa-7-thia-13-azabicyclo[15.2.2]henicosa-1(19),17,20-trien-15-yl]acetate;benzyl 2-[(8R,11S,14R)-8-acetyl-11-(2-methylpropyl)-10,13-dioxo-2-oxa-12-azabicyclo[14.2.2]icosa-1(18),16,19-trien-14-yl]acetate is CC(=O)[C@@H]1CCCCCOc2ccc(cc2)C[C@H](CC(=O)OCc2ccccc2)C(=O)N[C@@H](CC(C)C)C(=O)C1.CC(=O)[C@@H]1CCCCOc2ccc(cc2)C[C@H](CC(=O)OCc2ccccc2)C(=O)N[C@@H](C(C)C)C(=O)C1.CC(=O)[C@@H]1CCCCOc2ccc(cc2)C[C@H](CC(=O)c2ccc[nH]2)C(=O)N[C@@H](C(C)C)C(=O)C1.CC(=O)[C@@H]1CCCCOc2ccc(cc2)C[C@H](CS(=O)(=O)c2ccc(F)cc2)C(=O)N[C@@H](CC(C)C)C(=O)C1.CC(=O)[C@@H]1CSCCCCOc2ccc(cc2)C[C@H](CC(=O)OCc2ccccc2)C(=O)N[C@@H](C(C)C)C(=O)C1.

What is the InChIKey of (7R,10S,13S)-7-acetyl-13-[(4-fluorophenyl)sulfonylmethyl]-10-(2-methylpropyl)-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-triene-9,12-dione;(7R,10S,13R)-7-acetyl-13-[2-oxo-2-(1H-pyrrol-2-yl)ethyl]-10-propan-2-yl-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-triene-9,12-dione;benzyl 2-[(7R,10S,13R)-7-acetyl-9,12-dioxo-10-propan-2-yl-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-trien-13-yl]acetate;benzyl 2-[(9R,12S,15R)-9-acetyl-11,14-dioxo-12-propan-2-yl-2-oxa-7-thia-13-azabicyclo[15.2.2]henicosa-1(19),17,20-trien-15-yl]acetate;benzyl 2-[(8R,11S,14R)-8-acetyl-11-(2-methylpropyl)-10,13-dioxo-2-oxa-12-azabicyclo[14.2.2]icosa-1(18),16,19-trien-14-yl]acetate?

The InChIKey is ISCXFFCFXLAMNO-GNPBQLKZSA-N. The full InChI is InChI=1S/C33H43NO6.C32H41NO6S.C31H39NO6.C30H38FNO6S.C28H36N2O5/c1-23(2)18-30-31(36)20-27(24(3)35)12-8-5-9-17-39-29-15-13-25(14-16-29)19-28(33(38)34-30)21-32(37)40-22-26-10-6-4-7-11-26;1-22(2)31-29(35)18-27(23(3)34)21-40-16-8-7-15-38-28-13-11-24(12-14-28)17-26(32(37)33-31)19-30(36)39-20-25-9-5-4-6-10-25;1-21(2)30-28(34)18-25(22(3)33)11-7-8-16-37-27-14-12-23(13-15-27)17-26(31(36)32-30)19-29(35)38-20-24-9-5-4-6-10-24;1-20(2)16-28-29(34)18-23(21(3)33)6-4-5-15-38-26-11-7-22(8-12-26)17-24(30(35)32-28)19-39(36,37)27-13-9-25(31)10-14-27;1-18(2)27-26(33)16-21(19(3)31)7-4-5-14-35-23-11-9-20(10-12-23)15-22(28(34)30-27)17-25(32)24-8-6-13-29-24/h4,6-7,10-11,13-16,23,27-28,30H,5,8-9,12,17-22H2,1-3H3,(H,34,38);4-6,9-14,22,26-27,31H,7-8,15-21H2,1-3H3,(H,33,37);4-6,9-10,12-15,21,25-26,30H,7-8,11,16-20H2,1-3H3,(H,32,36);7-14,20,23-24,28H,4-6,15-19H2,1-3H3,(H,32,35);6,8-13,18,21-22,27,29H,4-5,7,14-17H2,1-3H3,(H,30,34)/t27-,28-,30+;26-,27+,31+;25-,26-,30+;23-,24-,28+;21-,22-,27+/m11111/s1.

What are the key properties of (7R,10S,13S)-7-acetyl-13-[(4-fluorophenyl)sulfonylmethyl]-10-(2-methylpropyl)-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-triene-9,12-dione;(7R,10S,13R)-7-acetyl-13-[2-oxo-2-(1H-pyrrol-2-yl)ethyl]-10-propan-2-yl-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-triene-9,12-dione;benzyl 2-[(7R,10S,13R)-7-acetyl-9,12-dioxo-10-propan-2-yl-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-trien-13-yl]acetate;benzyl 2-[(9R,12S,15R)-9-acetyl-11,14-dioxo-12-propan-2-yl-2-oxa-7-thia-13-azabicyclo[15.2.2]henicosa-1(19),17,20-trien-15-yl]acetate;benzyl 2-[(8R,11S,14R)-8-acetyl-11-(2-methylpropyl)-10,13-dioxo-2-oxa-12-azabicyclo[14.2.2]icosa-1(18),16,19-trien-14-yl]acetate?

(7R,10S,13S)-7-acetyl-13-[(4-fluorophenyl)sulfonylmethyl]-10-(2-methylpropyl)-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-triene-9,12-dione;(7R,10S,13R)-7-acetyl-13-[2-oxo-2-(1H-pyrrol-2-yl)ethyl]-10-propan-2-yl-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-triene-9,12-dione;benzyl 2-[(7R,10S,13R)-7-acetyl-9,12-dioxo-10-propan-2-yl-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-trien-13-yl]acetate;benzyl 2-[(9R,12S,15R)-9-acetyl-11,14-dioxo-12-propan-2-yl-2-oxa-7-thia-13-azabicyclo[15.2.2]henicosa-1(19),17,20-trien-15-yl]acetate;benzyl 2-[(8R,11S,14R)-8-acetyl-11-(2-methylpropyl)-10,13-dioxo-2-oxa-12-azabicyclo[14.2.2]icosa-1(18),16,19-trien-14-yl]acetate has a molecular weight of 2679.41 g/mol, XLogP of 24.69, 30 rotatable bonds, 6 hydrogen bond donors, and 30 hydrogen bond acceptors.

Where does this data come from?

All data for (7R,10S,13S)-7-acetyl-13-[(4-fluorophenyl)sulfonylmethyl]-10-(2-methylpropyl)-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-triene-9,12-dione;(7R,10S,13R)-7-acetyl-13-[2-oxo-2-(1H-pyrrol-2-yl)ethyl]-10-propan-2-yl-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-triene-9,12-dione;benzyl 2-[(7R,10S,13R)-7-acetyl-9,12-dioxo-10-propan-2-yl-2-oxa-11-azabicyclo[13.2.2]nonadeca-1(17),15,18-trien-13-yl]acetate;benzyl 2-[(9R,12S,15R)-9-acetyl-11,14-dioxo-12-propan-2-yl-2-oxa-7-thia-13-azabicyclo[15.2.2]henicosa-1(19),17,20-trien-15-yl]acetate;benzyl 2-[(8R,11S,14R)-8-acetyl-11-(2-methylpropyl)-10,13-dioxo-2-oxa-12-azabicyclo[14.2.2]icosa-1(18),16,19-trien-14-yl]acetate is sourced from PubChem (CID 158789759), the world's largest open chemistry database maintained by the National Library of Medicine (NIH).