Macro Cpyrimidine[9]

The pyrimidine ring occurs in such important compounds as cytosine, thymine, uracil, and the barbiturates. The arguments of the macro were selected such that these compounds can be typeset. Ring positions 1–6 are the positions to which R1–R6 are attached.

$\displaystyle \pyrimidine$$R1$$R2$$R3$$R4$$R5$$R6$QQD   $\displaystyle \pyrimidine$$H$O$H$O$R5$OQ$R8$Q

Arguments 1, 3, 5:
An argument of ``Q'' causes no action. All other argument values are used as the respective substituent formulas R1, R3, and R5.
Argument 2:
An argument of ``Q'' causes no action. An argument of ``O'' causes an outside double bond with an O to be drawn at position 2. All other argument values are used as the substituent formula R2 with a single bond.
Argument 4:
An argument of ``Q'' causes no action. An argument of ``O'' causes an outside double bond with an O to be drawn at position 4. All other argument values are used as the substituent formula R4 with a single bond.
Argument 6:
An argument of ``Q'' causes no action. An argument of ``O'' causes an outside double bond with an O to be drawn at position 6. All other argument values are used as the substituent formula R6 with a single bond.
Argument 7:
An argument of ``D'' prints a second bond between positions 1 and 2. All other argument values cause no action.
Argument 8:
An argument of ``Q'' causes no action. An argument of ``D'' prints a second bond between positions 3 and 4. All other argument values are used as the second substituent in position 5, R8.
Argument 9:
An argument of ``D'' prints a second bond between positions 5 and 6. All other argument values cause no action.