5-Amino-6-(5'-phosphoribosylamino)uracil

5-amino-6-(5'-phosphoribosylamino)uracil

formula | C_9H_15N_4O_9P_1 Hill formula | C_9H_15N_4O_9P name | 5-amino-6-(5'-phosphoribosylamino)uracil alternate names | 5-amino-6-(ribosylamino)-2, 4-(1H, 3H)-pyrimidinedione 5'-phosphate mass fractions | C (carbon) 30.5% | H (hydrogen) 4.27% | N (nitrogen) 15.8% | O (oxygen) 40.7% | P (phosphorus) 8.74%

Draw the Lewis structure of 5-amino-6-(5'-phosphoribosylamino)uracil. Start by drawing the overall structure of the molecule, ignoring potential double and triple bonds: Count the total valence electrons of the carbon (n_C, val = 4), hydrogen (n_H, val = 1), nitrogen (n_N, val = 5), oxygen (n_O, val = 6), and phosphorus (n_P, val = 5) atoms: 9 n_C, val + 15 n_H, val + 4 n_N, val + 9 n_O, val + n_P, val = 130 Calculate the number of electrons needed to completely fill the valence shells for carbon (n_C, full = 8), hydrogen (n_H, full = 2), nitrogen (n_N, full = 8), oxygen (n_O, full = 8), and phosphorus (n_P, full = 8): 9 n_C, full + 15 n_H, full + 4 n_N, full + 9 n_O, full + n_P, full = 214 Subtracting these two numbers shows that 214 - 130 = 84 bonding electrons are needed. Each bond has two electrons, so in addition to the 39 bonds already present in the diagram we expect to add 3 bonds. To minimize formal charge carbon wants 4 bonds and oxygen wants 2 bonds. Identify the atoms that want additional bonds and the number of electrons remaining on each atom: Add 3 bonds by pairing electrons between adjacent highlighted atoms. Additionally, atoms with large electronegativities can minimize their formal charge by forcing atoms with smaller electronegativities on period 3 or higher to expand their valence shells. The electronegativities of the atoms are 2.19 (phosphorus), 2.20 (hydrogen), 2.55 (carbon), 3.04 (nitrogen), and 3.44 (oxygen). Because the electronegativity of phosphorus is smaller than the electronegativity of oxygen, expand the valence shell of phosphorus to 5 bonds. Therefore we add a total of 4 bonds to the diagram: Answer: | |

molar mass | 354.21 g/mol

SMILES identifier | C([C@@H]1[C@H]([C@H](C(NC2=C(C(=O)NC(=O)N2)N)O1)O)O)OP(=O)(O)O