O=C(Nc1ccc2c(c1)OCO2)O[C@H]1C[C@@H]2CCN3C(=O)CCC[C@H](C1)[C@H]23
In analogy to the rule of five, it has been proposed that ideal fragments should follow the rule of three, in which the molecular weight of a fragment is <300, the c LogP is ≤3, the number of hydrogen bond donors is ≤3 and the number of hydrogen bond acceptors is ≤3. The molecule meets rule of three or not?