hexakis(dimethyl(phenyl)phosphanium);hexakis(methyl(diphenyl)phosphanium);bis(4-methyl-2-(5-methylpyrazol-2-id-3-yl)-5-phenylpyridine);bis(2-(4-methyl-3-phenylpyrazol-1-id-5-yl)-4-(2-methylpropyl)-5-phenylpyridine);bis(4-(2-methylpropyl)-5-phenyl-2-[3-phenyl-4-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine);bis(2-(5-methylpyrazol-2-id-3-yl)-5-phenyl-4-(2,3,3,3-tetradeuterio-2-methylpropyl)pyridine);hexakis(osmium(2+));bis(5-phenyl-4-[2,3,3,3-tetradeuterio-2-(trideuteriomethyl)propyl]-2-[3-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine);bis(5-phenyl-4-(trideuteriomethyl)-2-[3-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine)

C366H370F18N36Os6P12+12 — CID 158857934

About hexakis(dimethyl(phenyl)phosphanium);hexakis(methyl(diphenyl)phosphanium);bis(4-methyl-2-(5-methylpyrazol-2-id-3-yl)-5-phenylpyridine);bis(2-(4-methyl-3-phenylpyrazol-1-id-5-yl)-4-(2-methylpropyl)-5-phenylpyridine);bis(4-(2-methylpropyl)-5-phenyl-2-[3-phenyl-4-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine);bis(2-(5-methylpyrazol-2-id-3-yl)-5-phenyl-4-(2,3,3,3-tetradeuterio-2-methylpropyl)pyridine);hexakis(osmium(2+));bis(5-phenyl-4-[2,3,3,3-tetradeuterio-2-(trideuteriomethyl)propyl]-2-[3-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine);bis(5-phenyl-4-(trideuteriomethyl)-2-[3-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine)

hexakis(dimethyl(phenyl)phosphanium);hexakis(methyl(diphenyl)phosphanium);bis(4-methyl-2-(5-methylpyrazol-2-id-3-yl)-5-phenylpyridine);bis(2-(4-methyl-3-phenylpyrazol-1-id-5-yl)-4-(2-methylpropyl)-5-phenylpyridine);bis(4-(2-methylpropyl)-5-phenyl-2-[3-phenyl-4-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine);bis(2-(5-methylpyrazol-2-id-3-yl)-5-phenyl-4-(2,3,3,3-tetradeuterio-2-methylpropyl)pyridine);hexakis(osmium(2+));bis(5-phenyl-4-[2,3,3,3-tetradeuterio-2-(trideuteriomethyl)propyl]-2-[3-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine);bis(5-phenyl-4-(trideuteriomethyl)-2-[3-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine) (PubChem CID 158857934) has the molecular formula C366H370F18N36Os6P12+12 and a molecular weight of 7156.44 g/mol. Its IUPAC name is hexakis(dimethyl(phenyl)phosphanium);hexakis(methyl(diphenyl)phosphanium);bis(4-methyl-2-(5-methylpyrazol-2-id-3-yl)-5-phenylpyridine);bis(2-(4-methyl-3-phenylpyrazol-1-id-5-yl)-4-(2-methylpropyl)-5-phenylpyridine);bis(4-(2-methylpropyl)-5-phenyl-2-[3-phenyl-4-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine);bis(2-(5-methylpyrazol-2-id-3-yl)-5-phenyl-4-(2,3,3,3-tetradeuterio-2-methylpropyl)pyridine);hexakis(osmium(2+));bis(5-phenyl-4-[2,3,3,3-tetradeuterio-2-(trideuteriomethyl)propyl]-2-[3-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine);bis(5-phenyl-4-(trideuteriomethyl)-2-[3-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine).

Molecular Properties

• Compound Name: hexakis(dimethyl(phenyl)phosphanium);hexakis(methyl(diphenyl)phosphanium);bis(4-methyl-2-(5-methylpyrazol-2-id-3-yl)-5-phenylpyridine);bis(2-(4-methyl-3-phenylpyrazol-1-id-5-yl)-4-(2-methylpropyl)-5-phenylpyridine);bis(4-(2-methylpropyl)-5-phenyl-2-[3-phenyl-4-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine);bis(2-(5-methylpyrazol-2-id-3-yl)-5-phenyl-4-(2,3,3,3-tetradeuterio-2-methylpropyl)pyridine);hexakis(osmium(2+));bis(5-phenyl-4-[2,3,3,3-tetradeuterio-2-(trideuteriomethyl)propyl]-2-[3-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine);bis(5-phenyl-4-(trideuteriomethyl)-2-[3-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine)
• PubChem CID: 158857934
• Molecular Formula: C366H370F18N36Os6P12+12
• Molecular Weight: 7156.44 g/mol
• Exact Mass: 7162.60
• IUPAC Name: hexakis(dimethyl(phenyl)phosphanium);hexakis(methyl(diphenyl)phosphanium);bis(4-methyl-2-(5-methylpyrazol-2-id-3-yl)-5-phenylpyridine);bis(2-(4-methyl-3-phenylpyrazol-1-id-5-yl)-4-(2-methylpropyl)-5-phenylpyridine);bis(4-(2-methylpropyl)-5-phenyl-2-[3-phenyl-4-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine);bis(2-(5-methylpyrazol-2-id-3-yl)-5-phenyl-4-(2,3,3,3-tetradeuterio-2-methylpropyl)pyridine);hexakis(osmium(2+));bis(5-phenyl-4-[2,3,3,3-tetradeuterio-2-(trideuteriomethyl)propyl]-2-[3-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine);bis(5-phenyl-4-(trideuteriomethyl)-2-[3-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine)
• SMILES: CC(C)Cc1cc(-c2[n-]nc(-c3ccccc3)c2C(F)(F)F)ncc1-c1ccccc1.CC(C)Cc1cc(-c2[n-]nc(-c3ccccc3)c2C(F)(F)F)ncc1-c1ccccc1.C[PH+](C)c1ccccc1.C[PH+](C)c1ccccc1.C[PH+](C)c1ccccc1.C[PH+](C)c1ccccc1.C[PH+](C)c1ccccc1.C[PH+](C)c1ccccc1.C[PH+](c1ccccc1)c1ccccc1.C[PH+](c1ccccc1)c1ccccc1.C[PH+](c1ccccc1)c1ccccc1.C[PH+](c1ccccc1)c1ccccc1.C[PH+](c1ccccc1)c1ccccc1.C[PH+](c1ccccc1)c1ccccc1.Cc1c(-c2ccccc2)n[n-]c1-c1cc(CC(C)C)c(-c2ccccc2)cn1.Cc1c(-c2ccccc2)n[n-]c1-c1cc(CC(C)C)c(-c2ccccc2)cn1.Cc1cc(-c2cc(C)c(-c3ccccc3)cn2)[n-]n1.Cc1cc(-c2cc(C)c(-c3ccccc3)cn2)[n-]n1.[2H]C([2H])([2H])C([2H])(C)Cc1cc(-c2cc(C)n[n-]2)ncc1-c1ccccc1.[2H]C([2H])([2H])C([2H])(C)Cc1cc(-c2cc(C)n[n-]2)ncc1-c1ccccc1.[2H]C([2H])([2H])C([2H])(Cc1cc(-c2cc(C(F)(F)F)n[n-]2)ncc1-c1ccccc1)C([2H])([2H])[2H].[2H]C([2H])([2H])C([2H])(Cc1cc(-c2cc(C(F)(F)F)n[n-]2)ncc1-c1ccccc1)C([2H])([2H])[2H].[2H]C([2H])([2H])c1cc(-c2cc(C(F)(F)F)n[n-]2)ncc1-c1ccccc1.[2H]C([2H])([2H])c1cc(-c2cc(C(F)(F)F)n[n-]2)ncc1-c1ccccc1.[Os+2].[Os+2].[Os+2].[Os+2].[Os+2].[Os+2]
• InChI: InChI=1S/2C25H21F3N3.2C25H24N3.2C19H17F3N3.2C19H20N3.2C16H11F3N3.2C16H14N3.6C13H13P.6C8H11P.6Os/c2*1-16(2)13-19-14-21(29-15-20(19)17-9-5-3-6-10-17)24-22(25(26,27)28)23(30-31-24)18-11-7-4-8-12-18;2*1-17(2)14-21-15-23(26-16-22(21)19-10-6-4-7-11-19)25-18(3)24(27-28-25)20-12-8-5-9-13-20;2*1-12(2)8-14-9-16(17-10-18(25-24-17)19(20,21)22)23-11-15(14)13-6-4-3-5-7-13;2*1-13(2)9-16-11-18(19-10-14(3)21-22-19)20-12-17(16)15-7-5-4-6-8-15;2*1-10-7-13(14-8-15(22-21-14)16(17,18)19)20-9-12(10)11-5-3-2-4-6-11;2*1-11-8-15(16-9-12(2)18-19-16)17-10-14(11)13-6-4-3-5-7-13;6*1-14(12-8-4-2-5-9-12)13-10-6-3-7-11-13;6*1-9(2)8-6-4-3-5-7-8;;;;;;/h2*3-12,14-16H,13H2,1-2H3;2*4-13,15-17H,14H2,1-3H3;2*3-7,9-12H,8H2,1-2H3;2*4-8,10-13H,9H2,1-3H3;2*2-9H,1H3;2*3-10H,1-2H3;6*2-11H,1H3;6*3-7H,1-2H3;;;;;;/q12*-1;;;;;;;;;;;;;6*+2/p+12/i;;;;2*1D3,2D3,12D;2*1D3,13D;2*1D3
• InChIKey: SUVWQRSEMSRHJA-NVAYRUPASA-Z
• XLogP: 84.25
• TPSA: 478.56 Ų
• H-Bond Acceptors: 24
• Rotatable Bonds: 70
• Heavy Atoms: 438
• Complexity: —

Lipinski Rule of Five

3 violations

Rule	Value
MW ≤ 500	7156.44
LogP ≤ 5	84.25
H-Bond Donors ≤ 5	0
H-Bond Acceptors ≤ 10	24

Frequently Asked Questions

What is the IUPAC name of hexakis(dimethyl(phenyl)phosphanium);hexakis(methyl(diphenyl)phosphanium);bis(4-methyl-2-(5-methylpyrazol-2-id-3-yl)-5-phenylpyridine);bis(2-(4-methyl-3-phenylpyrazol-1-id-5-yl)-4-(2-methylpropyl)-5-phenylpyridine);bis(4-(2-methylpropyl)-5-phenyl-2-[3-phenyl-4-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine);bis(2-(5-methylpyrazol-2-id-3-yl)-5-phenyl-4-(2,3,3,3-tetradeuterio-2-methylpropyl)pyridine);hexakis(osmium(2+));bis(5-phenyl-4-[2,3,3,3-tetradeuterio-2-(trideuteriomethyl)propyl]-2-[3-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine);bis(5-phenyl-4-(trideuteriomethyl)-2-[3-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine)?

The IUPAC name of hexakis(dimethyl(phenyl)phosphanium);hexakis(methyl(diphenyl)phosphanium);bis(4-methyl-2-(5-methylpyrazol-2-id-3-yl)-5-phenylpyridine);bis(2-(4-methyl-3-phenylpyrazol-1-id-5-yl)-4-(2-methylpropyl)-5-phenylpyridine);bis(4-(2-methylpropyl)-5-phenyl-2-[3-phenyl-4-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine);bis(2-(5-methylpyrazol-2-id-3-yl)-5-phenyl-4-(2,3,3,3-tetradeuterio-2-methylpropyl)pyridine);hexakis(osmium(2+));bis(5-phenyl-4-[2,3,3,3-tetradeuterio-2-(trideuteriomethyl)propyl]-2-[3-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine);bis(5-phenyl-4-(trideuteriomethyl)-2-[3-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine) (CID 158857934) is hexakis(dimethyl(phenyl)phosphanium);hexakis(methyl(diphenyl)phosphanium);bis(4-methyl-2-(5-methylpyrazol-2-id-3-yl)-5-phenylpyridine);bis(2-(4-methyl-3-phenylpyrazol-1-id-5-yl)-4-(2-methylpropyl)-5-phenylpyridine);bis(4-(2-methylpropyl)-5-phenyl-2-[3-phenyl-4-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine);bis(2-(5-methylpyrazol-2-id-3-yl)-5-phenyl-4-(2,3,3,3-tetradeuterio-2-methylpropyl)pyridine);hexakis(osmium(2+));bis(5-phenyl-4-[2,3,3,3-tetradeuterio-2-(trideuteriomethyl)propyl]-2-[3-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine);bis(5-phenyl-4-(trideuteriomethyl)-2-[3-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine).

What is the SMILES notation for hexakis(dimethyl(phenyl)phosphanium);hexakis(methyl(diphenyl)phosphanium);bis(4-methyl-2-(5-methylpyrazol-2-id-3-yl)-5-phenylpyridine);bis(2-(4-methyl-3-phenylpyrazol-1-id-5-yl)-4-(2-methylpropyl)-5-phenylpyridine);bis(4-(2-methylpropyl)-5-phenyl-2-[3-phenyl-4-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine);bis(2-(5-methylpyrazol-2-id-3-yl)-5-phenyl-4-(2,3,3,3-tetradeuterio-2-methylpropyl)pyridine);hexakis(osmium(2+));bis(5-phenyl-4-[2,3,3,3-tetradeuterio-2-(trideuteriomethyl)propyl]-2-[3-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine);bis(5-phenyl-4-(trideuteriomethyl)-2-[3-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine)?

The canonical SMILES for hexakis(dimethyl(phenyl)phosphanium);hexakis(methyl(diphenyl)phosphanium);bis(4-methyl-2-(5-methylpyrazol-2-id-3-yl)-5-phenylpyridine);bis(2-(4-methyl-3-phenylpyrazol-1-id-5-yl)-4-(2-methylpropyl)-5-phenylpyridine);bis(4-(2-methylpropyl)-5-phenyl-2-[3-phenyl-4-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine);bis(2-(5-methylpyrazol-2-id-3-yl)-5-phenyl-4-(2,3,3,3-tetradeuterio-2-methylpropyl)pyridine);hexakis(osmium(2+));bis(5-phenyl-4-[2,3,3,3-tetradeuterio-2-(trideuteriomethyl)propyl]-2-[3-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine);bis(5-phenyl-4-(trideuteriomethyl)-2-[3-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine) is CC(C)Cc1cc(-c2[n-]nc(-c3ccccc3)c2C(F)(F)F)ncc1-c1ccccc1.CC(C)Cc1cc(-c2[n-]nc(-c3ccccc3)c2C(F)(F)F)ncc1-c1ccccc1.C[PH+](C)c1ccccc1.C[PH+](C)c1ccccc1.C[PH+](C)c1ccccc1.C[PH+](C)c1ccccc1.C[PH+](C)c1ccccc1.C[PH+](C)c1ccccc1.C[PH+](c1ccccc1)c1ccccc1.C[PH+](c1ccccc1)c1ccccc1.C[PH+](c1ccccc1)c1ccccc1.C[PH+](c1ccccc1)c1ccccc1.C[PH+](c1ccccc1)c1ccccc1.C[PH+](c1ccccc1)c1ccccc1.Cc1c(-c2ccccc2)n[n-]c1-c1cc(CC(C)C)c(-c2ccccc2)cn1.Cc1c(-c2ccccc2)n[n-]c1-c1cc(CC(C)C)c(-c2ccccc2)cn1.Cc1cc(-c2cc(C)c(-c3ccccc3)cn2)[n-]n1.Cc1cc(-c2cc(C)c(-c3ccccc3)cn2)[n-]n1.[2H]C([2H])([2H])C([2H])(C)Cc1cc(-c2cc(C)n[n-]2)ncc1-c1ccccc1.[2H]C([2H])([2H])C([2H])(C)Cc1cc(-c2cc(C)n[n-]2)ncc1-c1ccccc1.[2H]C([2H])([2H])C([2H])(Cc1cc(-c2cc(C(F)(F)F)n[n-]2)ncc1-c1ccccc1)C([2H])([2H])[2H].[2H]C([2H])([2H])C([2H])(Cc1cc(-c2cc(C(F)(F)F)n[n-]2)ncc1-c1ccccc1)C([2H])([2H])[2H].[2H]C([2H])([2H])c1cc(-c2cc(C(F)(F)F)n[n-]2)ncc1-c1ccccc1.[2H]C([2H])([2H])c1cc(-c2cc(C(F)(F)F)n[n-]2)ncc1-c1ccccc1.[Os+2].[Os+2].[Os+2].[Os+2].[Os+2].[Os+2].

What is the InChIKey of hexakis(dimethyl(phenyl)phosphanium);hexakis(methyl(diphenyl)phosphanium);bis(4-methyl-2-(5-methylpyrazol-2-id-3-yl)-5-phenylpyridine);bis(2-(4-methyl-3-phenylpyrazol-1-id-5-yl)-4-(2-methylpropyl)-5-phenylpyridine);bis(4-(2-methylpropyl)-5-phenyl-2-[3-phenyl-4-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine);bis(2-(5-methylpyrazol-2-id-3-yl)-5-phenyl-4-(2,3,3,3-tetradeuterio-2-methylpropyl)pyridine);hexakis(osmium(2+));bis(5-phenyl-4-[2,3,3,3-tetradeuterio-2-(trideuteriomethyl)propyl]-2-[3-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine);bis(5-phenyl-4-(trideuteriomethyl)-2-[3-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine)?

The InChIKey is SUVWQRSEMSRHJA-NVAYRUPASA-Z. The full InChI is InChI=1S/2C25H21F3N3.2C25H24N3.2C19H17F3N3.2C19H20N3.2C16H11F3N3.2C16H14N3.6C13H13P.6C8H11P.6Os/c2*1-16(2)13-19-14-21(29-15-20(19)17-9-5-3-6-10-17)24-22(25(26,27)28)23(30-31-24)18-11-7-4-8-12-18;2*1-17(2)14-21-15-23(26-16-22(21)19-10-6-4-7-11-19)25-18(3)24(27-28-25)20-12-8-5-9-13-20;2*1-12(2)8-14-9-16(17-10-18(25-24-17)19(20,21)22)23-11-15(14)13-6-4-3-5-7-13;2*1-13(2)9-16-11-18(19-10-14(3)21-22-19)20-12-17(16)15-7-5-4-6-8-15;2*1-10-7-13(14-8-15(22-21-14)16(17,18)19)20-9-12(10)11-5-3-2-4-6-11;2*1-11-8-15(16-9-12(2)18-19-16)17-10-14(11)13-6-4-3-5-7-13;6*1-14(12-8-4-2-5-9-12)13-10-6-3-7-11-13;6*1-9(2)8-6-4-3-5-7-8;;;;;;/h2*3-12,14-16H,13H2,1-2H3;2*4-13,15-17H,14H2,1-3H3;2*3-7,9-12H,8H2,1-2H3;2*4-8,10-13H,9H2,1-3H3;2*2-9H,1H3;2*3-10H,1-2H3;6*2-11H,1H3;6*3-7H,1-2H3;;;;;;/q12*-1;;;;;;;;;;;;;6*+2/p+12/i;;;;2*1D3,2D3,12D;2*1D3,13D;2*1D3;;;;;;;;;;;;;;;;;;;;.

What are the key properties of hexakis(dimethyl(phenyl)phosphanium);hexakis(methyl(diphenyl)phosphanium);bis(4-methyl-2-(5-methylpyrazol-2-id-3-yl)-5-phenylpyridine);bis(2-(4-methyl-3-phenylpyrazol-1-id-5-yl)-4-(2-methylpropyl)-5-phenylpyridine);bis(4-(2-methylpropyl)-5-phenyl-2-[3-phenyl-4-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine);bis(2-(5-methylpyrazol-2-id-3-yl)-5-phenyl-4-(2,3,3,3-tetradeuterio-2-methylpropyl)pyridine);hexakis(osmium(2+));bis(5-phenyl-4-[2,3,3,3-tetradeuterio-2-(trideuteriomethyl)propyl]-2-[3-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine);bis(5-phenyl-4-(trideuteriomethyl)-2-[3-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine)?

hexakis(dimethyl(phenyl)phosphanium);hexakis(methyl(diphenyl)phosphanium);bis(4-methyl-2-(5-methylpyrazol-2-id-3-yl)-5-phenylpyridine);bis(2-(4-methyl-3-phenylpyrazol-1-id-5-yl)-4-(2-methylpropyl)-5-phenylpyridine);bis(4-(2-methylpropyl)-5-phenyl-2-[3-phenyl-4-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine);bis(2-(5-methylpyrazol-2-id-3-yl)-5-phenyl-4-(2,3,3,3-tetradeuterio-2-methylpropyl)pyridine);hexakis(osmium(2+));bis(5-phenyl-4-[2,3,3,3-tetradeuterio-2-(trideuteriomethyl)propyl]-2-[3-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine);bis(5-phenyl-4-(trideuteriomethyl)-2-[3-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine) has a molecular weight of 7156.44 g/mol, XLogP of 84.25, 70 rotatable bonds, 0 hydrogen bond donors, and 24 hydrogen bond acceptors.

Where does this data come from?

All data for hexakis(dimethyl(phenyl)phosphanium);hexakis(methyl(diphenyl)phosphanium);bis(4-methyl-2-(5-methylpyrazol-2-id-3-yl)-5-phenylpyridine);bis(2-(4-methyl-3-phenylpyrazol-1-id-5-yl)-4-(2-methylpropyl)-5-phenylpyridine);bis(4-(2-methylpropyl)-5-phenyl-2-[3-phenyl-4-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine);bis(2-(5-methylpyrazol-2-id-3-yl)-5-phenyl-4-(2,3,3,3-tetradeuterio-2-methylpropyl)pyridine);hexakis(osmium(2+));bis(5-phenyl-4-[2,3,3,3-tetradeuterio-2-(trideuteriomethyl)propyl]-2-[3-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine);bis(5-phenyl-4-(trideuteriomethyl)-2-[3-(trifluoromethyl)pyrazol-1-id-5-yl]pyridine) is sourced from PubChem (CID 158857934), the world's largest open chemistry database maintained by the National Library of Medicine (NIH).