U73
ATOM  O11  C10  N9   C3   N4   C5   S2   C1   C6   C8 
ATOM  C7   C12  C13  C14  C15  C16  N17  C18
CONNECT -  O11  C10  N9  C3  N4  C5  C1  S2  C3 +
CONNECT  C10  C12  C13  C14  C15  C16  N17  C18  C13
CONNECT  C1   C6  C8
CONNECT  C6   C7