About 2-[3-(1-benzyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-9-yl)propyl]-6-[[2-[[3-[3-(1-benzyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-9-yl)propyl]-5-tert-butyl-2-hydroxyphenyl]methylideneamino]cyclohexyl]iminomethyl]-4-tert-butylphenol;2-[3-(7-benzyl-2,3,5,6-tetrahydroimidazo[1,2-a]imidazol-4-ium-1-yl)propyl]-4-tert-butyl-6-[[2-[(3,5-ditert-butyl-2-hydroxyphenyl)methylideneamino]cyclohexyl]iminomethyl]phenol;4-tert-butyl-2-[[2-[[5-tert-butyl-3-[3-(9-ethyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]-2-hydroxyphenyl]methylideneamino]cyclohexyl]iminomethyl]-6-[3-(9-ethyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]phenol;4-tert-butyl-2-[[2-[[5-tert-butyl-3-[3-(3,4,6,7,8,9-hexahydro-2H-pyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]-2-hydroxyphenyl]methylideneamino]cyclohexyl]iminomethyl]-6-[3-(3,4,6,7,8,9-hexahydro-2H-pyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]phenol;carbanide;chromium;oxalic acid;tetrahydrate
2-[3-(1-benzyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-9-yl)propyl]-6-[[2-[[3-[3-(1-benzyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-9-yl)propyl]-5-tert-butyl-2-hydroxyphenyl]methylideneamino]cyclohexyl]iminomethyl]-4-tert-butylphenol;2-[3-(7-benzyl-2,3,5,6-tetrahydroimidazo[1,2-a]imidazol-4-ium-1-yl)propyl]-4-tert-butyl-6-[[2-[(3,5-ditert-butyl-2-hydroxyphenyl)methylideneamino]cyclohexyl]iminomethyl]phenol;4-tert-butyl-2-[[2-[[5-tert-butyl-3-[3-(9-ethyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]-2-hydroxyphenyl]methylideneamino]cyclohexyl]iminomethyl]-6-[3-(9-ethyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]phenol;4-tert-butyl-2-[[2-[[5-tert-butyl-3-[3-(3,4,6,7,8,9-hexahydro-2H-pyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]-2-hydroxyphenyl]methylideneamino]cyclohexyl]iminomethyl]-6-[3-(3,4,6,7,8,9-hexahydro-2H-pyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]phenol;carbanide;chromium;oxalic acid;tetrahydrate (PubChem CID 161461577) has the molecular formula C220H333Cr4N29O28+4
and a molecular weight of 4040.24 g/mol. Its IUPAC name is 2-[3-(1-benzyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-9-yl)propyl]-6-[[2-[[3-[3-(1-benzyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-9-yl)propyl]-5-tert-butyl-2-hydroxyphenyl]methylideneamino]cyclohexyl]iminomethyl]-4-tert-butylphenol;2-[3-(7-benzyl-2,3,5,6-tetrahydroimidazo[1,2-a]imidazol-4-ium-1-yl)propyl]-4-tert-butyl-6-[[2-[(3,5-ditert-butyl-2-hydroxyphenyl)methylideneamino]cyclohexyl]iminomethyl]phenol;4-tert-butyl-2-[[2-[[5-tert-butyl-3-[3-(9-ethyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]-2-hydroxyphenyl]methylideneamino]cyclohexyl]iminomethyl]-6-[3-(9-ethyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]phenol;4-tert-butyl-2-[[2-[[5-tert-butyl-3-[3-(3,4,6,7,8,9-hexahydro-2H-pyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]-2-hydroxyphenyl]methylideneamino]cyclohexyl]iminomethyl]-6-[3-(3,4,6,7,8,9-hexahydro-2H-pyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]phenol;carbanide;chromium;oxalic acid;tetrahydrate.
Frequently Asked Questions
What is the IUPAC name of 2-[3-(1-benzyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-9-yl)propyl]-6-[[2-[[3-[3-(1-benzyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-9-yl)propyl]-5-tert-butyl-2-hydroxyphenyl]methylideneamino]cyclohexyl]iminomethyl]-4-tert-butylphenol;2-[3-(7-benzyl-2,3,5,6-tetrahydroimidazo[1,2-a]imidazol-4-ium-1-yl)propyl]-4-tert-butyl-6-[[2-[(3,5-ditert-butyl-2-hydroxyphenyl)methylideneamino]cyclohexyl]iminomethyl]phenol;4-tert-butyl-2-[[2-[[5-tert-butyl-3-[3-(9-ethyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]-2-hydroxyphenyl]methylideneamino]cyclohexyl]iminomethyl]-6-[3-(9-ethyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]phenol;4-tert-butyl-2-[[2-[[5-tert-butyl-3-[3-(3,4,6,7,8,9-hexahydro-2H-pyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]-2-hydroxyphenyl]methylideneamino]cyclohexyl]iminomethyl]-6-[3-(3,4,6,7,8,9-hexahydro-2H-pyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]phenol;carbanide;chromium;oxalic acid;tetrahydrate?
The IUPAC name of 2-[3-(1-benzyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-9-yl)propyl]-6-[[2-[[3-[3-(1-benzyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-9-yl)propyl]-5-tert-butyl-2-hydroxyphenyl]methylideneamino]cyclohexyl]iminomethyl]-4-tert-butylphenol;2-[3-(7-benzyl-2,3,5,6-tetrahydroimidazo[1,2-a]imidazol-4-ium-1-yl)propyl]-4-tert-butyl-6-[[2-[(3,5-ditert-butyl-2-hydroxyphenyl)methylideneamino]cyclohexyl]iminomethyl]phenol;4-tert-butyl-2-[[2-[[5-tert-butyl-3-[3-(9-ethyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]-2-hydroxyphenyl]methylideneamino]cyclohexyl]iminomethyl]-6-[3-(9-ethyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]phenol;4-tert-butyl-2-[[2-[[5-tert-butyl-3-[3-(3,4,6,7,8,9-hexahydro-2H-pyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]-2-hydroxyphenyl]methylideneamino]cyclohexyl]iminomethyl]-6-[3-(3,4,6,7,8,9-hexahydro-2H-pyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]phenol;carbanide;chromium;oxalic acid;tetrahydrate (CID 161461577) is 2-[3-(1-benzyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-9-yl)propyl]-6-[[2-[[3-[3-(1-benzyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-9-yl)propyl]-5-tert-butyl-2-hydroxyphenyl]methylideneamino]cyclohexyl]iminomethyl]-4-tert-butylphenol;2-[3-(7-benzyl-2,3,5,6-tetrahydroimidazo[1,2-a]imidazol-4-ium-1-yl)propyl]-4-tert-butyl-6-[[2-[(3,5-ditert-butyl-2-hydroxyphenyl)methylideneamino]cyclohexyl]iminomethyl]phenol;4-tert-butyl-2-[[2-[[5-tert-butyl-3-[3-(9-ethyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]-2-hydroxyphenyl]methylideneamino]cyclohexyl]iminomethyl]-6-[3-(9-ethyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]phenol;4-tert-butyl-2-[[2-[[5-tert-butyl-3-[3-(3,4,6,7,8,9-hexahydro-2H-pyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]-2-hydroxyphenyl]methylideneamino]cyclohexyl]iminomethyl]-6-[3-(3,4,6,7,8,9-hexahydro-2H-pyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]phenol;carbanide;chromium;oxalic acid;tetrahydrate.
What is the SMILES notation for 2-[3-(1-benzyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-9-yl)propyl]-6-[[2-[[3-[3-(1-benzyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-9-yl)propyl]-5-tert-butyl-2-hydroxyphenyl]methylideneamino]cyclohexyl]iminomethyl]-4-tert-butylphenol;2-[3-(7-benzyl-2,3,5,6-tetrahydroimidazo[1,2-a]imidazol-4-ium-1-yl)propyl]-4-tert-butyl-6-[[2-[(3,5-ditert-butyl-2-hydroxyphenyl)methylideneamino]cyclohexyl]iminomethyl]phenol;4-tert-butyl-2-[[2-[[5-tert-butyl-3-[3-(9-ethyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]-2-hydroxyphenyl]methylideneamino]cyclohexyl]iminomethyl]-6-[3-(9-ethyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]phenol;4-tert-butyl-2-[[2-[[5-tert-butyl-3-[3-(3,4,6,7,8,9-hexahydro-2H-pyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]-2-hydroxyphenyl]methylideneamino]cyclohexyl]iminomethyl]-6-[3-(3,4,6,7,8,9-hexahydro-2H-pyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]phenol;carbanide;chromium;oxalic acid;tetrahydrate?
The canonical SMILES for 2-[3-(1-benzyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-9-yl)propyl]-6-[[2-[[3-[3-(1-benzyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-9-yl)propyl]-5-tert-butyl-2-hydroxyphenyl]methylideneamino]cyclohexyl]iminomethyl]-4-tert-butylphenol;2-[3-(7-benzyl-2,3,5,6-tetrahydroimidazo[1,2-a]imidazol-4-ium-1-yl)propyl]-4-tert-butyl-6-[[2-[(3,5-ditert-butyl-2-hydroxyphenyl)methylideneamino]cyclohexyl]iminomethyl]phenol;4-tert-butyl-2-[[2-[[5-tert-butyl-3-[3-(9-ethyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]-2-hydroxyphenyl]methylideneamino]cyclohexyl]iminomethyl]-6-[3-(9-ethyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]phenol;4-tert-butyl-2-[[2-[[5-tert-butyl-3-[3-(3,4,6,7,8,9-hexahydro-2H-pyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]-2-hydroxyphenyl]methylideneamino]cyclohexyl]iminomethyl]-6-[3-(3,4,6,7,8,9-hexahydro-2H-pyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]phenol;carbanide;chromium;oxalic acid;tetrahydrate is CC(C)(C)c1cc(/C=N/C2CCCCC2/N=C/c2cc(C(C)(C)C)cc(C(C)(C)C)c2O)c(O)c(CCCN2CC[N+]3=C2N(Cc2ccccc2)CC3)c1.CC(C)(C)c1cc(/C=N/C2CCCCC2/N=C/c2cc(C(C)(C)C)cc(CCCN3CCC[N+]4=C3N(Cc3ccccc3)CCC4)c2O)c(O)c(CCCN2CCC[N+]3=C2N(Cc2ccccc2)CCC3)c1.CC(C)(C)c1cc(/C=N/C2CCCCC2/N=C/c2cc(C(C)(C)C)cc(CCCN3CCC[N+]4=C3NCCC4)c2O)c(O)c(CCCN2CCC[N+]3=C2NCCC3)c1.CCN1CCC[N+]2=C1N(CCCc1cc(C(C)(C)C)cc(/C=N/C3CCCCC3/N=C/c3cc(C(C)(C)C)cc(CCCN4CCC[N+]5=C4N(CC)CCC5)c3O)c1O)CCC2.O.O.O.O.O=C(O)C(=O)O.O=C(O)C(=O)O.O=C(O)C(=O)O.O=C(O)C(=O)O.[CH3-].[CH3-].[CH3-].[Cr].[Cr].[Cr].[Cr].
What is the InChIKey of 2-[3-(1-benzyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-9-yl)propyl]-6-[[2-[[3-[3-(1-benzyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-9-yl)propyl]-5-tert-butyl-2-hydroxyphenyl]methylideneamino]cyclohexyl]iminomethyl]-4-tert-butylphenol;2-[3-(7-benzyl-2,3,5,6-tetrahydroimidazo[1,2-a]imidazol-4-ium-1-yl)propyl]-4-tert-butyl-6-[[2-[(3,5-ditert-butyl-2-hydroxyphenyl)methylideneamino]cyclohexyl]iminomethyl]phenol;4-tert-butyl-2-[[2-[[5-tert-butyl-3-[3-(9-ethyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]-2-hydroxyphenyl]methylideneamino]cyclohexyl]iminomethyl]-6-[3-(9-ethyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]phenol;4-tert-butyl-2-[[2-[[5-tert-butyl-3-[3-(3,4,6,7,8,9-hexahydro-2H-pyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]-2-hydroxyphenyl]methylideneamino]cyclohexyl]iminomethyl]-6-[3-(3,4,6,7,8,9-hexahydro-2H-pyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]phenol;carbanide;chromium;oxalic acid;tetrahydrate?
The InChIKey is CJGPGNCUXZECFL-UHFFFAOYSA-U. The full InChI is InChI=1S/C62H84N8O2.C52H80N8O2.C48H72N8O2.C47H65N5O2.4C2H2O4.3CH3.4Cr.4H2O/c1-61(2,3)53-39-49(25-15-29-65-31-17-33-67-35-19-37-69(59(65)67)45-47-21-9-7-10-22-47)57(71)51(41-53)43-63-55-27-13-14-28-56(55)64-44-52-42-54(62(4,5)6)40-50(58(52)72)26-16-30-66-32-18-34-68-36-20-38-70(60(66)68)46-48-23-11-8-12-24-48;1-9-55-25-15-27-59-31-17-29-57(49(55)59)23-13-19-39-33-43(51(3,4)5)35-41(47(39)61)37-53-45-21-11-12-22-46(45)54-38-42-36-44(52(6,7)8)34-40(48(42)62)20-14-24-58-30-18-32-60-28-16-26-56(10-2)50(58)60;1-47(2,3)39-29-35(15-9-21-53-25-13-27-55-23-11-19-49-45(53)55)43(57)37(31-39)33-51-41-17-7-8-18-42(41)52-34-38-32-40(48(4,5)6)30-36(44(38)58)16-10-22-54-26-14-28-56-24-12-20-50-46(54)56;1-45(2,3)37-26-34(18-15-21-50-22-23-51-24-25-52(44(50)51)32-33-16-11-10-12-17-33)42(53)35(27-37)30-48-40-19-13-14-20-41(40)49-31-36-28-38(46(4,5)6)29-39(43(36)54)47(7,8)9;4*3-1(4)2(5)6;;;;;;;;;;;/h7-12,21-24,39-44,55-56H,13-20,25-38,45-46H2,1-6H3;33-38,45-46H,9-32H2,1-8H3;29-34,41-42H,7-28H2,1-6H3,(H2,51,52,57,58);10-12,16-17,26-31,40-41H,13-15,18-25,32H2,1-9H3,(H-,48,49,53,54);4*(H,3,4)(H,5,6);3*1H3;;;;;4*1H2/q;;;;;;;;3*-1;;;;;;;;/p+7.
What are the key properties of 2-[3-(1-benzyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-9-yl)propyl]-6-[[2-[[3-[3-(1-benzyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-9-yl)propyl]-5-tert-butyl-2-hydroxyphenyl]methylideneamino]cyclohexyl]iminomethyl]-4-tert-butylphenol;2-[3-(7-benzyl-2,3,5,6-tetrahydroimidazo[1,2-a]imidazol-4-ium-1-yl)propyl]-4-tert-butyl-6-[[2-[(3,5-ditert-butyl-2-hydroxyphenyl)methylideneamino]cyclohexyl]iminomethyl]phenol;4-tert-butyl-2-[[2-[[5-tert-butyl-3-[3-(9-ethyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]-2-hydroxyphenyl]methylideneamino]cyclohexyl]iminomethyl]-6-[3-(9-ethyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]phenol;4-tert-butyl-2-[[2-[[5-tert-butyl-3-[3-(3,4,6,7,8,9-hexahydro-2H-pyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]-2-hydroxyphenyl]methylideneamino]cyclohexyl]iminomethyl]-6-[3-(3,4,6,7,8,9-hexahydro-2H-pyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]phenol;carbanide;chromium;oxalic acid;tetrahydrate?
2-[3-(1-benzyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-9-yl)propyl]-6-[[2-[[3-[3-(1-benzyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-9-yl)propyl]-5-tert-butyl-2-hydroxyphenyl]methylideneamino]cyclohexyl]iminomethyl]-4-tert-butylphenol;2-[3-(7-benzyl-2,3,5,6-tetrahydroimidazo[1,2-a]imidazol-4-ium-1-yl)propyl]-4-tert-butyl-6-[[2-[(3,5-ditert-butyl-2-hydroxyphenyl)methylideneamino]cyclohexyl]iminomethyl]phenol;4-tert-butyl-2-[[2-[[5-tert-butyl-3-[3-(9-ethyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]-2-hydroxyphenyl]methylideneamino]cyclohexyl]iminomethyl]-6-[3-(9-ethyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]phenol;4-tert-butyl-2-[[2-[[5-tert-butyl-3-[3-(3,4,6,7,8,9-hexahydro-2H-pyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]-2-hydroxyphenyl]methylideneamino]cyclohexyl]iminomethyl]-6-[3-(3,4,6,7,8,9-hexahydro-2H-pyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]phenol;carbanide;chromium;oxalic acid;tetrahydrate has a molecular weight of 4040.24 g/mol, XLogP of 28.55, 52 rotatable bonds, 18 hydrogen bond donors, and 38 hydrogen bond acceptors.
Where does this data come from?
All data for 2-[3-(1-benzyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-9-yl)propyl]-6-[[2-[[3-[3-(1-benzyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-9-yl)propyl]-5-tert-butyl-2-hydroxyphenyl]methylideneamino]cyclohexyl]iminomethyl]-4-tert-butylphenol;2-[3-(7-benzyl-2,3,5,6-tetrahydroimidazo[1,2-a]imidazol-4-ium-1-yl)propyl]-4-tert-butyl-6-[[2-[(3,5-ditert-butyl-2-hydroxyphenyl)methylideneamino]cyclohexyl]iminomethyl]phenol;4-tert-butyl-2-[[2-[[5-tert-butyl-3-[3-(9-ethyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]-2-hydroxyphenyl]methylideneamino]cyclohexyl]iminomethyl]-6-[3-(9-ethyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]phenol;4-tert-butyl-2-[[2-[[5-tert-butyl-3-[3-(3,4,6,7,8,9-hexahydro-2H-pyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]-2-hydroxyphenyl]methylideneamino]cyclohexyl]iminomethyl]-6-[3-(3,4,6,7,8,9-hexahydro-2H-pyrimido[1,2-a]pyrimidin-5-ium-1-yl)propyl]phenol;carbanide;chromium;oxalic acid;tetrahydrate is sourced from PubChem (CID 161461577), the world's largest open chemistry database maintained by the National Library of Medicine (NIH).