(2E)-1-[6-[2-[3-[(2S)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[2-[[(2S)-2-[[(2R)-2-acetamido-3-methylsulfanylpropanoyl]amino]propanoyl]amino]acetyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-3-amino-3-oxopropyl]sulfanyl-2,5-dioxopyrrolidin-1-yl]ethylamino]-6-oxohexyl]-2-[(2E,4E)-5-(1-ethyl-3,3-dimethyl-5-sulfoindol-1-ium-2-yl)penta-2,4-dienylidene]-3,3-dimethylindole-5-sulfonic acid

C107H180N45O23S4+ — CID 122461260

About (2E)-1-[6-[2-[3-[(2S)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[2-[[(2S)-2-[[(2R)-2-acetamido-3-methylsulfanylpropanoyl]amino]propanoyl]amino]acetyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-3-amino-3-oxopropyl]sulfanyl-2,5-dioxopyrrolidin-1-yl]ethylamino]-6-oxohexyl]-2-[(2E,4E)-5-(1-ethyl-3,3-dimethyl-5-sulfoindol-1-ium-2-yl)penta-2,4-dienylidene]-3,3-dimethylindole-5-sulfonic acid

(2E)-1-[6-[2-[3-[(2S)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[2-[[(2S)-2-[[(2R)-2-acetamido-3-methylsulfanylpropanoyl]amino]propanoyl]amino]acetyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-3-amino-3-oxopropyl]sulfanyl-2,5-dioxopyrrolidin-1-yl]ethylamino]-6-oxohexyl]-2-[(2E,4E)-5-(1-ethyl-3,3-dimethyl-5-sulfoindol-1-ium-2-yl)penta-2,4-dienylidene]-3,3-dimethylindole-5-sulfonic acid (PubChem CID 122461260) has the molecular formula C107H180N45O23S4+ and a molecular weight of 2593.18 g/mol. Its IUPAC name is (2E)-1-[6-[2-[3-[(2S)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[2-[[(2S)-2-[[(2R)-2-acetamido-3-methylsulfanylpropanoyl]amino]propanoyl]amino]acetyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-3-amino-3-oxopropyl]sulfanyl-2,5-dioxopyrrolidin-1-yl]ethylamino]-6-oxohexyl]-2-[(2E,4E)-5-(1-ethyl-3,3-dimethyl-5-sulfoindol-1-ium-2-yl)penta-2,4-dienylidene]-3,3-dimethylindole-5-sulfonic acid.

Molecular Properties

• Compound Name: (2E)-1-[6-[2-[3-[(2S)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[2-[[(2S)-2-[[(2R)-2-acetamido-3-methylsulfanylpropanoyl]amino]propanoyl]amino]acetyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-3-amino-3-oxopropyl]sulfanyl-2,5-dioxopyrrolidin-1-yl]ethylamino]-6-oxohexyl]-2-[(2E,4E)-5-(1-ethyl-3,3-dimethyl-5-sulfoindol-1-ium-2-yl)penta-2,4-dienylidene]-3,3-dimethylindole-5-sulfonic acid
• PubChem CID: 122461260
• Molecular Formula: C107H180N45O23S4+
• Molecular Weight: 2593.18 g/mol
• Exact Mass: 2591.32
• IUPAC Name: (2E)-1-[6-[2-[3-[(2S)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[2-[[(2S)-2-[[(2R)-2-acetamido-3-methylsulfanylpropanoyl]amino]propanoyl]amino]acetyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-3-amino-3-oxopropyl]sulfanyl-2,5-dioxopyrrolidin-1-yl]ethylamino]-6-oxohexyl]-2-[(2E,4E)-5-(1-ethyl-3,3-dimethyl-5-sulfoindol-1-ium-2-yl)penta-2,4-dienylidene]-3,3-dimethylindole-5-sulfonic acid
• SMILES: [H]/N=C(\N)NCCC[C@@H](NC(=O)CNC(=O)[C@H](C)NC(=O)[C@H](CSC)NC(C)=O)C(=O)N[C@H](CCCN/C(N)=N/[H])C(=O)N[C@H](CCCN/C(N)=N/[H])C(=O)N[C@H](CCCN/C(N)=N/[H])C(=O)N[C@H](CCCN/C(N)=N/[H])C(=O)N[C@H](CCCN/C(N)=N/[H])C(=O)N[C@H](CCCN/C(N)=N/[H])C(=O)N[C@H](CCCN/C(N)=N/[H])C(=O)N[C@H](CCCN/C(N)=N/[H])C(=O)N[C@H](CSC1CC(=O)N(CCNC(=O)CCCCCN2/C(=C/C=C/C=C/C3=[N+](CC)c4ccc(S(=O)(=O)O)cc4C3(C)C)C(C)(C)c3cc(S(=O)(=O)O)ccc32)C1=O)C(N)=O
• InChI: InChI=1S/C107H179N45O23S4/c1-9-150-76-39-37-61(178(170,171)172)53-63(76)106(4,5)79(150)34-12-10-13-35-80-107(6,7)64-54-62(179(173,174)175)38-40-77(64)151(80)51-15-11-14-36-81(154)127-50-52-152-83(156)55-78(96(152)169)177-58-74(84(108)157)149-94(167)73(33-24-49-136-105(125)126)148-93(166)72(32-23-48-135-104(123)124)147-92(165)71(31-22-47-134-103(121)122)146-91(164)70(30-21-46-133-102(119)120)145-90(163)69(29-20-45-132-101(117)118)144-89(162)68(28-19-44-131-100(115)116)143-88(161)67(27-18-43-130-99(113)114)142-87(160)66(26-17-42-129-98(111)112)141-86(159)65(25-16-41-128-97(109)110)140-82(155)56-137-85(158)59(2)138-95(168)75(57-176-8)139-60(3)153/h10,12-13,34-35,37-40,53-54,59,65-75,78H,9,11,14-33,36,41-52,55-58H2,1-8H3,(H53-,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,128,129,130,131,132,133,134,135,136,137,138,139,140,141,142,143,144,145,146,147,148,149,153,154,155,157,158,159,160,161,162,163,164,165,166,167,168,170,171,172,173,174,175)/p+1/t59-,65+,66+,67+,68+,69+,70+,71+,72+,73+,74+,75-,78?/m0/s1
• InChIKey: AWBOFDVMGZFRMJ-ZAGOYFLHSA-O
• XLogP: -8.90
• TPSA: 1159.96 Ų
• H-Bond Donors: 44
• H-Bond Acceptors: 33
• Rotatable Bonds: 82
• Heavy Atoms: 179
• Complexity: —

Lipinski Rule of Five

3 violations

Rule	Value
MW ≤ 500	2593.18
LogP ≤ 5	-8.90
H-Bond Donors ≤ 5	44
H-Bond Acceptors ≤ 10	33

Computed Properties (RDKit)

• Structural Alerts: {'alert_name': 'Aliphatic_long_chain', 'substructure': 'N/A'}, {'alert_name': 'imine_1', 'substructure': 'N/A'}, {'alert_name': 'imine_2', 'substructure': 'N/A'}, {'alert_name': 'phthalimide', 'substructure': 'N/A'}, {'alert_name': 'polyene', 'substructure': 'N/A'}

Frequently Asked Questions

What is the IUPAC name of (2E)-1-[6-[2-[3-[(2S)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[2-[[(2S)-2-[[(2R)-2-acetamido-3-methylsulfanylpropanoyl]amino]propanoyl]amino]acetyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-3-amino-3-oxopropyl]sulfanyl-2,5-dioxopyrrolidin-1-yl]ethylamino]-6-oxohexyl]-2-[(2E,4E)-5-(1-ethyl-3,3-dimethyl-5-sulfoindol-1-ium-2-yl)penta-2,4-dienylidene]-3,3-dimethylindole-5-sulfonic acid?

The IUPAC name of (2E)-1-[6-[2-[3-[(2S)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[2-[[(2S)-2-[[(2R)-2-acetamido-3-methylsulfanylpropanoyl]amino]propanoyl]amino]acetyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-3-amino-3-oxopropyl]sulfanyl-2,5-dioxopyrrolidin-1-yl]ethylamino]-6-oxohexyl]-2-[(2E,4E)-5-(1-ethyl-3,3-dimethyl-5-sulfoindol-1-ium-2-yl)penta-2,4-dienylidene]-3,3-dimethylindole-5-sulfonic acid (CID 122461260) is (2E)-1-[6-[2-[3-[(2S)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[2-[[(2S)-2-[[(2R)-2-acetamido-3-methylsulfanylpropanoyl]amino]propanoyl]amino]acetyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-3-amino-3-oxopropyl]sulfanyl-2,5-dioxopyrrolidin-1-yl]ethylamino]-6-oxohexyl]-2-[(2E,4E)-5-(1-ethyl-3,3-dimethyl-5-sulfoindol-1-ium-2-yl)penta-2,4-dienylidene]-3,3-dimethylindole-5-sulfonic acid.

What is the SMILES notation for (2E)-1-[6-[2-[3-[(2S)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[2-[[(2S)-2-[[(2R)-2-acetamido-3-methylsulfanylpropanoyl]amino]propanoyl]amino]acetyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-3-amino-3-oxopropyl]sulfanyl-2,5-dioxopyrrolidin-1-yl]ethylamino]-6-oxohexyl]-2-[(2E,4E)-5-(1-ethyl-3,3-dimethyl-5-sulfoindol-1-ium-2-yl)penta-2,4-dienylidene]-3,3-dimethylindole-5-sulfonic acid?

The canonical SMILES for (2E)-1-[6-[2-[3-[(2S)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[2-[[(2S)-2-[[(2R)-2-acetamido-3-methylsulfanylpropanoyl]amino]propanoyl]amino]acetyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-3-amino-3-oxopropyl]sulfanyl-2,5-dioxopyrrolidin-1-yl]ethylamino]-6-oxohexyl]-2-[(2E,4E)-5-(1-ethyl-3,3-dimethyl-5-sulfoindol-1-ium-2-yl)penta-2,4-dienylidene]-3,3-dimethylindole-5-sulfonic acid is [H]/N=C(\N)NCCC[C@@H](NC(=O)CNC(=O)[C@H](C)NC(=O)[C@H](CSC)NC(C)=O)C(=O)N[C@H](CCCN/C(N)=N/[H])C(=O)N[C@H](CCCN/C(N)=N/[H])C(=O)N[C@H](CCCN/C(N)=N/[H])C(=O)N[C@H](CCCN/C(N)=N/[H])C(=O)N[C@H](CCCN/C(N)=N/[H])C(=O)N[C@H](CCCN/C(N)=N/[H])C(=O)N[C@H](CCCN/C(N)=N/[H])C(=O)N[C@H](CCCN/C(N)=N/[H])C(=O)N[C@H](CSC1CC(=O)N(CCNC(=O)CCCCCN2/C(=C/C=C/C=C/C3=[N+](CC)c4ccc(S(=O)(=O)O)cc4C3(C)C)C(C)(C)c3cc(S(=O)(=O)O)ccc32)C1=O)C(N)=O.

What is the InChIKey of (2E)-1-[6-[2-[3-[(2S)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[2-[[(2S)-2-[[(2R)-2-acetamido-3-methylsulfanylpropanoyl]amino]propanoyl]amino]acetyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-3-amino-3-oxopropyl]sulfanyl-2,5-dioxopyrrolidin-1-yl]ethylamino]-6-oxohexyl]-2-[(2E,4E)-5-(1-ethyl-3,3-dimethyl-5-sulfoindol-1-ium-2-yl)penta-2,4-dienylidene]-3,3-dimethylindole-5-sulfonic acid?

The InChIKey is AWBOFDVMGZFRMJ-ZAGOYFLHSA-O. The full InChI is InChI=1S/C107H179N45O23S4/c1-9-150-76-39-37-61(178(170,171)172)53-63(76)106(4,5)79(150)34-12-10-13-35-80-107(6,7)64-54-62(179(173,174)175)38-40-77(64)151(80)51-15-11-14-36-81(154)127-50-52-152-83(156)55-78(96(152)169)177-58-74(84(108)157)149-94(167)73(33-24-49-136-105(125)126)148-93(166)72(32-23-48-135-104(123)124)147-92(165)71(31-22-47-134-103(121)122)146-91(164)70(30-21-46-133-102(119)120)145-90(163)69(29-20-45-132-101(117)118)144-89(162)68(28-19-44-131-100(115)116)143-88(161)67(27-18-43-130-99(113)114)142-87(160)66(26-17-42-129-98(111)112)141-86(159)65(25-16-41-128-97(109)110)140-82(155)56-137-85(158)59(2)138-95(168)75(57-176-8)139-60(3)153/h10,12-13,34-35,37-40,53-54,59,65-75,78H,9,11,14-33,36,41-52,55-58H2,1-8H3,(H53-,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,128,129,130,131,132,133,134,135,136,137,138,139,140,141,142,143,144,145,146,147,148,149,153,154,155,157,158,159,160,161,162,163,164,165,166,167,168,170,171,172,173,174,175)/p+1/t59-,65+,66+,67+,68+,69+,70+,71+,72+,73+,74+,75-,78?/m0/s1.

What are the key properties of (2E)-1-[6-[2-[3-[(2S)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[2-[[(2S)-2-[[(2R)-2-acetamido-3-methylsulfanylpropanoyl]amino]propanoyl]amino]acetyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-3-amino-3-oxopropyl]sulfanyl-2,5-dioxopyrrolidin-1-yl]ethylamino]-6-oxohexyl]-2-[(2E,4E)-5-(1-ethyl-3,3-dimethyl-5-sulfoindol-1-ium-2-yl)penta-2,4-dienylidene]-3,3-dimethylindole-5-sulfonic acid?

(2E)-1-[6-[2-[3-[(2S)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[2-[[(2S)-2-[[(2R)-2-acetamido-3-methylsulfanylpropanoyl]amino]propanoyl]amino]acetyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-3-amino-3-oxopropyl]sulfanyl-2,5-dioxopyrrolidin-1-yl]ethylamino]-6-oxohexyl]-2-[(2E,4E)-5-(1-ethyl-3,3-dimethyl-5-sulfoindol-1-ium-2-yl)penta-2,4-dienylidene]-3,3-dimethylindole-5-sulfonic acid has a molecular weight of 2593.18 g/mol, XLogP of -8.90, 82 rotatable bonds, 44 hydrogen bond donors, and 33 hydrogen bond acceptors.

Where does this data come from?

All data for (2E)-1-[6-[2-[3-[(2S)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[(2R)-2-[[2-[[(2S)-2-[[(2R)-2-acetamido-3-methylsulfanylpropanoyl]amino]propanoyl]amino]acetyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-3-amino-3-oxopropyl]sulfanyl-2,5-dioxopyrrolidin-1-yl]ethylamino]-6-oxohexyl]-2-[(2E,4E)-5-(1-ethyl-3,3-dimethyl-5-sulfoindol-1-ium-2-yl)penta-2,4-dienylidene]-3,3-dimethylindole-5-sulfonic acid is sourced from PubChem (CID 122461260), the world's largest open chemistry database maintained by the National Library of Medicine (NIH).