25-methyl-21-(4-methylphenyl)-N,N,11,15-tetraphenyl-11,15,21-triaza-1-boraheptacyclo[14.11.1.02,14.04,12.05,10.020,28.022,27]octacosa-2,4(12),5,7,9,13,16,18,20(28),22(27),23,25-dodecaen-18-amine;11,15,21,25-tetraphenyl-11,15,21,25-tetraza-1-boranonacyclo[18.14.1.02,14.04,12.05,10.016,35.022,34.024,32.026,31]pentatriaconta-2,4(12),5,7,9,13,16(35),17,19,22,24(32),26,28,30,33-pentadecaene;trimethyl-(11,15,21,25-tetraphenyl-11,15,21,25-tetraza-1-boranonacyclo[18.14.1.02,14.04,12.05,10.016,35.022,34.024,32.026,31]pentatriaconta-2,4(12),5,7,9,13,16,18,20(35),22,24(32),26,28,30,33-pentadecaen-18-yl)silane;trimethyl-(11,15,21-triphenyl-11,15,21-triaza-1-boraheptacyclo[14.11.1.02,14.04,12.05,10.020,28.022,27]octacosa-2,4(12),5,7,9,13,16,18,20(28),22,24,26-dodecaen-18-yl)silane

C212H155B4N15Si2 — CID 158336570

About 25-methyl-21-(4-methylphenyl)-N,N,11,15-tetraphenyl-11,15,21-triaza-1-boraheptacyclo[14.11.1.02,14.04,12.05,10.020,28.022,27]octacosa-2,4(12),5,7,9,13,16,18,20(28),22(27),23,25-dodecaen-18-amine;11,15,21,25-tetraphenyl-11,15,21,25-tetraza-1-boranonacyclo[18.14.1.02,14.04,12.05,10.016,35.022,34.024,32.026,31]pentatriaconta-2,4(12),5,7,9,13,16(35),17,19,22,24(32),26,28,30,33-pentadecaene;trimethyl-(11,15,21,25-tetraphenyl-11,15,21,25-tetraza-1-boranonacyclo[18.14.1.02,14.04,12.05,10.016,35.022,34.024,32.026,31]pentatriaconta-2,4(12),5,7,9,13,16,18,20(35),22,24(32),26,28,30,33-pentadecaen-18-yl)silane;trimethyl-(11,15,21-triphenyl-11,15,21-triaza-1-boraheptacyclo[14.11.1.02,14.04,12.05,10.020,28.022,27]octacosa-2,4(12),5,7,9,13,16,18,20(28),22,24,26-dodecaen-18-yl)silane

25-methyl-21-(4-methylphenyl)-N,N,11,15-tetraphenyl-11,15,21-triaza-1-boraheptacyclo[14.11.1.02,14.04,12.05,10.020,28.022,27]octacosa-2,4(12),5,7,9,13,16,18,20(28),22(27),23,25-dodecaen-18-amine;11,15,21,25-tetraphenyl-11,15,21,25-tetraza-1-boranonacyclo[18.14.1.02,14.04,12.05,10.016,35.022,34.024,32.026,31]pentatriaconta-2,4(12),5,7,9,13,16(35),17,19,22,24(32),26,28,30,33-pentadecaene;trimethyl-(11,15,21,25-tetraphenyl-11,15,21,25-tetraza-1-boranonacyclo[18.14.1.02,14.04,12.05,10.016,35.022,34.024,32.026,31]pentatriaconta-2,4(12),5,7,9,13,16,18,20(35),22,24(32),26,28,30,33-pentadecaen-18-yl)silane;trimethyl-(11,15,21-triphenyl-11,15,21-triaza-1-boraheptacyclo[14.11.1.02,14.04,12.05,10.020,28.022,27]octacosa-2,4(12),5,7,9,13,16,18,20(28),22,24,26-dodecaen-18-yl)silane (PubChem CID 158336570) has the molecular formula C212H155B4N15Si2 and a molecular weight of 3012.10 g/mol. Its IUPAC name is 25-methyl-21-(4-methylphenyl)-N,N,11,15-tetraphenyl-11,15,21-triaza-1-boraheptacyclo[14.11.1.02,14.04,12.05,10.020,28.022,27]octacosa-2,4(12),5,7,9,13,16,18,20(28),22(27),23,25-dodecaen-18-amine;11,15,21,25-tetraphenyl-11,15,21,25-tetraza-1-boranonacyclo[18.14.1.02,14.04,12.05,10.016,35.022,34.024,32.026,31]pentatriaconta-2,4(12),5,7,9,13,16(35),17,19,22,24(32),26,28,30,33-pentadecaene;trimethyl-(11,15,21,25-tetraphenyl-11,15,21,25-tetraza-1-boranonacyclo[18.14.1.02,14.04,12.05,10.016,35.022,34.024,32.026,31]pentatriaconta-2,4(12),5,7,9,13,16,18,20(35),22,24(32),26,28,30,33-pentadecaen-18-yl)silane;trimethyl-(11,15,21-triphenyl-11,15,21-triaza-1-boraheptacyclo[14.11.1.02,14.04,12.05,10.020,28.022,27]octacosa-2,4(12),5,7,9,13,16,18,20(28),22,24,26-dodecaen-18-yl)silane.

Molecular Properties

• Compound Name: 25-methyl-21-(4-methylphenyl)-N,N,11,15-tetraphenyl-11,15,21-triaza-1-boraheptacyclo[14.11.1.02,14.04,12.05,10.020,28.022,27]octacosa-2,4(12),5,7,9,13,16,18,20(28),22(27),23,25-dodecaen-18-amine;11,15,21,25-tetraphenyl-11,15,21,25-tetraza-1-boranonacyclo[18.14.1.02,14.04,12.05,10.016,35.022,34.024,32.026,31]pentatriaconta-2,4(12),5,7,9,13,16(35),17,19,22,24(32),26,28,30,33-pentadecaene;trimethyl-(11,15,21,25-tetraphenyl-11,15,21,25-tetraza-1-boranonacyclo[18.14.1.02,14.04,12.05,10.016,35.022,34.024,32.026,31]pentatriaconta-2,4(12),5,7,9,13,16,18,20(35),22,24(32),26,28,30,33-pentadecaen-18-yl)silane;trimethyl-(11,15,21-triphenyl-11,15,21-triaza-1-boraheptacyclo[14.11.1.02,14.04,12.05,10.020,28.022,27]octacosa-2,4(12),5,7,9,13,16,18,20(28),22,24,26-dodecaen-18-yl)silane
• PubChem CID: 158336570
• Molecular Formula: C212H155B4N15Si2
• Molecular Weight: 3012.10 g/mol
• Exact Mass: 3010.25
• IUPAC Name: 25-methyl-21-(4-methylphenyl)-N,N,11,15-tetraphenyl-11,15,21-triaza-1-boraheptacyclo[14.11.1.02,14.04,12.05,10.020,28.022,27]octacosa-2,4(12),5,7,9,13,16,18,20(28),22(27),23,25-dodecaen-18-amine;11,15,21,25-tetraphenyl-11,15,21,25-tetraza-1-boranonacyclo[18.14.1.02,14.04,12.05,10.016,35.022,34.024,32.026,31]pentatriaconta-2,4(12),5,7,9,13,16(35),17,19,22,24(32),26,28,30,33-pentadecaene;trimethyl-(11,15,21,25-tetraphenyl-11,15,21,25-tetraza-1-boranonacyclo[18.14.1.02,14.04,12.05,10.016,35.022,34.024,32.026,31]pentatriaconta-2,4(12),5,7,9,13,16,18,20(35),22,24(32),26,28,30,33-pentadecaen-18-yl)silane;trimethyl-(11,15,21-triphenyl-11,15,21-triaza-1-boraheptacyclo[14.11.1.02,14.04,12.05,10.020,28.022,27]octacosa-2,4(12),5,7,9,13,16,18,20(28),22,24,26-dodecaen-18-yl)silane
• SMILES: C[Si](C)(C)c1cc2c3c(c1)N(c1ccccc1)c1cc4c(cc1B3c1cc3c5ccccc5n(-c5ccccc5)c3cc1N2c1ccccc1)c1ccccc1n4-c1ccccc1.C[Si](C)(C)c1cc2c3c(c1)N(c1ccccc1)c1cc4c(cc1B3c1ccccc1N2c1ccccc1)c1ccccc1n4-c1ccccc1.Cc1ccc(N2c3ccc(C)cc3B3c4cc5c6ccccc6n(-c6ccccc6)c5cc4N(c4ccccc4)c4cc(N(c5ccccc5)c5ccccc5)cc2c43)cc1.c1ccc(N2c3cc4c(cc3B3c5cc6c7ccccc7n(-c7ccccc7)c6cc5N(c5ccccc5)c5cccc2c53)c2ccccc2n4-c2ccccc2)cc1
• InChI: InChI=1S/C57H43BN4Si.C56H41BN4.C54H35BN4.C45H36BN3Si/c1-63(2,3)42-32-55-57-56(33-42)62(41-26-14-7-15-27-41)54-37-52-46(44-29-17-19-31-50(44)60(52)39-22-10-5-11-23-39)35-48(54)58(57)47-34-45-43-28-16-18-30-49(43)59(38-20-8-4-9-21-38)51(45)36-53(47)61(55)40-24-12-6-13-25-40;1-38-27-30-44(31-28-38)60-51-32-29-39(2)33-48(51)57-49-36-47-46-25-15-16-26-50(46)59(42-21-11-5-12-22-42)52(47)37-53(49)61(43-23-13-6-14-24-43)55-35-45(34-54(60)56(55)57)58(40-17-7-3-8-18-40)41-19-9-4-10-20-41;1-5-18-36(19-6-1)56-46-28-15-13-26-40(46)42-32-44-52(34-50(42)56)58(38-22-9-3-10-23-38)48-30-17-31-49-54(48)55(44)45-33-43-41-27-14-16-29-47(41)57(37-20-7-2-8-21-37)51(43)35-53(45)59(49)39-24-11-4-12-25-39;1-50(2,3)34-27-43-45-44(28-34)49(33-21-11-6-12-22-33)42-30-41-36(35-23-13-15-25-39(35)47(41)31-17-7-4-8-18-31)29-38(42)46(45)37-24-14-16-26-40(37)48(43)32-19-9-5-10-20-32/h4-37H,1-3H3;3-37H,1-2H3;1-35H;4-30H,1-3H3
• InChIKey: GQQQVJCXMXWQRN-UHFFFAOYSA-N
• XLogP: 46.84
• TPSA: 58.74 Ų
• H-Bond Acceptors: 15
• Rotatable Bonds: 19
• Heavy Atoms: 233
• Complexity: —

Lipinski Rule of Five

3 violations

Rule	Value
MW ≤ 500	3012.10
LogP ≤ 5	46.84
H-Bond Donors ≤ 5	0
H-Bond Acceptors ≤ 10	15

Computed Properties (RDKit)

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

Frequently Asked Questions

What is the IUPAC name of 25-methyl-21-(4-methylphenyl)-N,N,11,15-tetraphenyl-11,15,21-triaza-1-boraheptacyclo[14.11.1.02,14.04,12.05,10.020,28.022,27]octacosa-2,4(12),5,7,9,13,16,18,20(28),22(27),23,25-dodecaen-18-amine;11,15,21,25-tetraphenyl-11,15,21,25-tetraza-1-boranonacyclo[18.14.1.02,14.04,12.05,10.016,35.022,34.024,32.026,31]pentatriaconta-2,4(12),5,7,9,13,16(35),17,19,22,24(32),26,28,30,33-pentadecaene;trimethyl-(11,15,21,25-tetraphenyl-11,15,21,25-tetraza-1-boranonacyclo[18.14.1.02,14.04,12.05,10.016,35.022,34.024,32.026,31]pentatriaconta-2,4(12),5,7,9,13,16,18,20(35),22,24(32),26,28,30,33-pentadecaen-18-yl)silane;trimethyl-(11,15,21-triphenyl-11,15,21-triaza-1-boraheptacyclo[14.11.1.02,14.04,12.05,10.020,28.022,27]octacosa-2,4(12),5,7,9,13,16,18,20(28),22,24,26-dodecaen-18-yl)silane?

The IUPAC name of 25-methyl-21-(4-methylphenyl)-N,N,11,15-tetraphenyl-11,15,21-triaza-1-boraheptacyclo[14.11.1.02,14.04,12.05,10.020,28.022,27]octacosa-2,4(12),5,7,9,13,16,18,20(28),22(27),23,25-dodecaen-18-amine;11,15,21,25-tetraphenyl-11,15,21,25-tetraza-1-boranonacyclo[18.14.1.02,14.04,12.05,10.016,35.022,34.024,32.026,31]pentatriaconta-2,4(12),5,7,9,13,16(35),17,19,22,24(32),26,28,30,33-pentadecaene;trimethyl-(11,15,21,25-tetraphenyl-11,15,21,25-tetraza-1-boranonacyclo[18.14.1.02,14.04,12.05,10.016,35.022,34.024,32.026,31]pentatriaconta-2,4(12),5,7,9,13,16,18,20(35),22,24(32),26,28,30,33-pentadecaen-18-yl)silane;trimethyl-(11,15,21-triphenyl-11,15,21-triaza-1-boraheptacyclo[14.11.1.02,14.04,12.05,10.020,28.022,27]octacosa-2,4(12),5,7,9,13,16,18,20(28),22,24,26-dodecaen-18-yl)silane (CID 158336570) is 25-methyl-21-(4-methylphenyl)-N,N,11,15-tetraphenyl-11,15,21-triaza-1-boraheptacyclo[14.11.1.02,14.04,12.05,10.020,28.022,27]octacosa-2,4(12),5,7,9,13,16,18,20(28),22(27),23,25-dodecaen-18-amine;11,15,21,25-tetraphenyl-11,15,21,25-tetraza-1-boranonacyclo[18.14.1.02,14.04,12.05,10.016,35.022,34.024,32.026,31]pentatriaconta-2,4(12),5,7,9,13,16(35),17,19,22,24(32),26,28,30,33-pentadecaene;trimethyl-(11,15,21,25-tetraphenyl-11,15,21,25-tetraza-1-boranonacyclo[18.14.1.02,14.04,12.05,10.016,35.022,34.024,32.026,31]pentatriaconta-2,4(12),5,7,9,13,16,18,20(35),22,24(32),26,28,30,33-pentadecaen-18-yl)silane;trimethyl-(11,15,21-triphenyl-11,15,21-triaza-1-boraheptacyclo[14.11.1.02,14.04,12.05,10.020,28.022,27]octacosa-2,4(12),5,7,9,13,16,18,20(28),22,24,26-dodecaen-18-yl)silane.

What is the SMILES notation for 25-methyl-21-(4-methylphenyl)-N,N,11,15-tetraphenyl-11,15,21-triaza-1-boraheptacyclo[14.11.1.02,14.04,12.05,10.020,28.022,27]octacosa-2,4(12),5,7,9,13,16,18,20(28),22(27),23,25-dodecaen-18-amine;11,15,21,25-tetraphenyl-11,15,21,25-tetraza-1-boranonacyclo[18.14.1.02,14.04,12.05,10.016,35.022,34.024,32.026,31]pentatriaconta-2,4(12),5,7,9,13,16(35),17,19,22,24(32),26,28,30,33-pentadecaene;trimethyl-(11,15,21,25-tetraphenyl-11,15,21,25-tetraza-1-boranonacyclo[18.14.1.02,14.04,12.05,10.016,35.022,34.024,32.026,31]pentatriaconta-2,4(12),5,7,9,13,16,18,20(35),22,24(32),26,28,30,33-pentadecaen-18-yl)silane;trimethyl-(11,15,21-triphenyl-11,15,21-triaza-1-boraheptacyclo[14.11.1.02,14.04,12.05,10.020,28.022,27]octacosa-2,4(12),5,7,9,13,16,18,20(28),22,24,26-dodecaen-18-yl)silane?

The canonical SMILES for 25-methyl-21-(4-methylphenyl)-N,N,11,15-tetraphenyl-11,15,21-triaza-1-boraheptacyclo[14.11.1.02,14.04,12.05,10.020,28.022,27]octacosa-2,4(12),5,7,9,13,16,18,20(28),22(27),23,25-dodecaen-18-amine;11,15,21,25-tetraphenyl-11,15,21,25-tetraza-1-boranonacyclo[18.14.1.02,14.04,12.05,10.016,35.022,34.024,32.026,31]pentatriaconta-2,4(12),5,7,9,13,16(35),17,19,22,24(32),26,28,30,33-pentadecaene;trimethyl-(11,15,21,25-tetraphenyl-11,15,21,25-tetraza-1-boranonacyclo[18.14.1.02,14.04,12.05,10.016,35.022,34.024,32.026,31]pentatriaconta-2,4(12),5,7,9,13,16,18,20(35),22,24(32),26,28,30,33-pentadecaen-18-yl)silane;trimethyl-(11,15,21-triphenyl-11,15,21-triaza-1-boraheptacyclo[14.11.1.02,14.04,12.05,10.020,28.022,27]octacosa-2,4(12),5,7,9,13,16,18,20(28),22,24,26-dodecaen-18-yl)silane is C[Si](C)(C)c1cc2c3c(c1)N(c1ccccc1)c1cc4c(cc1B3c1cc3c5ccccc5n(-c5ccccc5)c3cc1N2c1ccccc1)c1ccccc1n4-c1ccccc1.C[Si](C)(C)c1cc2c3c(c1)N(c1ccccc1)c1cc4c(cc1B3c1ccccc1N2c1ccccc1)c1ccccc1n4-c1ccccc1.Cc1ccc(N2c3ccc(C)cc3B3c4cc5c6ccccc6n(-c6ccccc6)c5cc4N(c4ccccc4)c4cc(N(c5ccccc5)c5ccccc5)cc2c43)cc1.c1ccc(N2c3cc4c(cc3B3c5cc6c7ccccc7n(-c7ccccc7)c6cc5N(c5ccccc5)c5cccc2c53)c2ccccc2n4-c2ccccc2)cc1.

What is the InChIKey of 25-methyl-21-(4-methylphenyl)-N,N,11,15-tetraphenyl-11,15,21-triaza-1-boraheptacyclo[14.11.1.02,14.04,12.05,10.020,28.022,27]octacosa-2,4(12),5,7,9,13,16,18,20(28),22(27),23,25-dodecaen-18-amine;11,15,21,25-tetraphenyl-11,15,21,25-tetraza-1-boranonacyclo[18.14.1.02,14.04,12.05,10.016,35.022,34.024,32.026,31]pentatriaconta-2,4(12),5,7,9,13,16(35),17,19,22,24(32),26,28,30,33-pentadecaene;trimethyl-(11,15,21,25-tetraphenyl-11,15,21,25-tetraza-1-boranonacyclo[18.14.1.02,14.04,12.05,10.016,35.022,34.024,32.026,31]pentatriaconta-2,4(12),5,7,9,13,16,18,20(35),22,24(32),26,28,30,33-pentadecaen-18-yl)silane;trimethyl-(11,15,21-triphenyl-11,15,21-triaza-1-boraheptacyclo[14.11.1.02,14.04,12.05,10.020,28.022,27]octacosa-2,4(12),5,7,9,13,16,18,20(28),22,24,26-dodecaen-18-yl)silane?

The InChIKey is GQQQVJCXMXWQRN-UHFFFAOYSA-N. The full InChI is InChI=1S/C57H43BN4Si.C56H41BN4.C54H35BN4.C45H36BN3Si/c1-63(2,3)42-32-55-57-56(33-42)62(41-26-14-7-15-27-41)54-37-52-46(44-29-17-19-31-50(44)60(52)39-22-10-5-11-23-39)35-48(54)58(57)47-34-45-43-28-16-18-30-49(43)59(38-20-8-4-9-21-38)51(45)36-53(47)61(55)40-24-12-6-13-25-40;1-38-27-30-44(31-28-38)60-51-32-29-39(2)33-48(51)57-49-36-47-46-25-15-16-26-50(46)59(42-21-11-5-12-22-42)52(47)37-53(49)61(43-23-13-6-14-24-43)55-35-45(34-54(60)56(55)57)58(40-17-7-3-8-18-40)41-19-9-4-10-20-41;1-5-18-36(19-6-1)56-46-28-15-13-26-40(46)42-32-44-52(34-50(42)56)58(38-22-9-3-10-23-38)48-30-17-31-49-54(48)55(44)45-33-43-41-27-14-16-29-47(41)57(37-20-7-2-8-21-37)51(43)35-53(45)59(49)39-24-11-4-12-25-39;1-50(2,3)34-27-43-45-44(28-34)49(33-21-11-6-12-22-33)42-30-41-36(35-23-13-15-25-39(35)47(41)31-17-7-4-8-18-31)29-38(42)46(45)37-24-14-16-26-40(37)48(43)32-19-9-5-10-20-32/h4-37H,1-3H3;3-37H,1-2H3;1-35H;4-30H,1-3H3.

What are the key properties of 25-methyl-21-(4-methylphenyl)-N,N,11,15-tetraphenyl-11,15,21-triaza-1-boraheptacyclo[14.11.1.02,14.04,12.05,10.020,28.022,27]octacosa-2,4(12),5,7,9,13,16,18,20(28),22(27),23,25-dodecaen-18-amine;11,15,21,25-tetraphenyl-11,15,21,25-tetraza-1-boranonacyclo[18.14.1.02,14.04,12.05,10.016,35.022,34.024,32.026,31]pentatriaconta-2,4(12),5,7,9,13,16(35),17,19,22,24(32),26,28,30,33-pentadecaene;trimethyl-(11,15,21,25-tetraphenyl-11,15,21,25-tetraza-1-boranonacyclo[18.14.1.02,14.04,12.05,10.016,35.022,34.024,32.026,31]pentatriaconta-2,4(12),5,7,9,13,16,18,20(35),22,24(32),26,28,30,33-pentadecaen-18-yl)silane;trimethyl-(11,15,21-triphenyl-11,15,21-triaza-1-boraheptacyclo[14.11.1.02,14.04,12.05,10.020,28.022,27]octacosa-2,4(12),5,7,9,13,16,18,20(28),22,24,26-dodecaen-18-yl)silane?

25-methyl-21-(4-methylphenyl)-N,N,11,15-tetraphenyl-11,15,21-triaza-1-boraheptacyclo[14.11.1.02,14.04,12.05,10.020,28.022,27]octacosa-2,4(12),5,7,9,13,16,18,20(28),22(27),23,25-dodecaen-18-amine;11,15,21,25-tetraphenyl-11,15,21,25-tetraza-1-boranonacyclo[18.14.1.02,14.04,12.05,10.016,35.022,34.024,32.026,31]pentatriaconta-2,4(12),5,7,9,13,16(35),17,19,22,24(32),26,28,30,33-pentadecaene;trimethyl-(11,15,21,25-tetraphenyl-11,15,21,25-tetraza-1-boranonacyclo[18.14.1.02,14.04,12.05,10.016,35.022,34.024,32.026,31]pentatriaconta-2,4(12),5,7,9,13,16,18,20(35),22,24(32),26,28,30,33-pentadecaen-18-yl)silane;trimethyl-(11,15,21-triphenyl-11,15,21-triaza-1-boraheptacyclo[14.11.1.02,14.04,12.05,10.020,28.022,27]octacosa-2,4(12),5,7,9,13,16,18,20(28),22,24,26-dodecaen-18-yl)silane has a molecular weight of 3012.10 g/mol, XLogP of 46.84, 19 rotatable bonds, 0 hydrogen bond donors, and 15 hydrogen bond acceptors.

Where does this data come from?

All data for 25-methyl-21-(4-methylphenyl)-N,N,11,15-tetraphenyl-11,15,21-triaza-1-boraheptacyclo[14.11.1.02,14.04,12.05,10.020,28.022,27]octacosa-2,4(12),5,7,9,13,16,18,20(28),22(27),23,25-dodecaen-18-amine;11,15,21,25-tetraphenyl-11,15,21,25-tetraza-1-boranonacyclo[18.14.1.02,14.04,12.05,10.016,35.022,34.024,32.026,31]pentatriaconta-2,4(12),5,7,9,13,16(35),17,19,22,24(32),26,28,30,33-pentadecaene;trimethyl-(11,15,21,25-tetraphenyl-11,15,21,25-tetraza-1-boranonacyclo[18.14.1.02,14.04,12.05,10.016,35.022,34.024,32.026,31]pentatriaconta-2,4(12),5,7,9,13,16,18,20(35),22,24(32),26,28,30,33-pentadecaen-18-yl)silane;trimethyl-(11,15,21-triphenyl-11,15,21-triaza-1-boraheptacyclo[14.11.1.02,14.04,12.05,10.020,28.022,27]octacosa-2,4(12),5,7,9,13,16,18,20(28),22,24,26-dodecaen-18-yl)silane is sourced from PubChem (CID 158336570), the world's largest open chemistry database maintained by the National Library of Medicine (NIH).