1. A drug, characterized by (a) a compound represented by a formula (I): a salt or solution acceptable to the drug, wherein P is hydrogen or a group of samples to be formed； a 1 is cr1ar1b, s or O； A2 is cr2ar2b, s or O； A3 is cr3ar3b, s or O； A4 is independent cr4ar4b, s or O； The number of heteroatoms of ring atoms composed of nitrogen atoms near A1, A2, A3, A4, A1 and carbon atoms near A4 is 1 or 2, respectively； R1a and r1b are independent hydrogen, halogen, tar or similar substances； R2A and r2b are independent hydrogen, halogen, tar, Or similar；R3a and R3b are independent hydrogen, halogen, tar or similar substances； R4A is independent hydrogen, halogen, tar or similar substances； r4b is independent hydrogen, halogen, tar or similar substances； R3a and R3b can be combined with adjacent carbon atoms to form aromatic or odor free carbon； n is an integer from 1 to 2； R1 is or similar to combination (b) with anti epidemic activity, You can treat or prevent influenza with acceptable salt or solution on the drug and / or antibody with anti influenza activity.Un medicamento caracterizado en que (A) un compuesto representado por la fórmula (I): su sal farmacéuticamente aceptable, o un solvato del mismo, en donde P es hidrógeno o un grupo para formar un profármaco； A1 es CR1AR1B, S u O； A2 es CR2AR2B, S u O； A3 es CR3AR3B, S u O； A4 es cada uno independientemente CR4AR4B, S u O； el número de heteroátomos entre los átomos constituyentes del anillo que consiste de A1, A2, A3, A4, átomo de nitrógeno adyacente a A1 y átomo de carbono adyacente a A4 es 1 o 2； R1A y R1B son cada uno independientemente hidrógeno, halógeno, alquilo o similares； R2A y R2B son cada uno independientemente hidrógeno, halógeno, alquilo, o similares； R3A y R3B son cada uno independientemente hidrógeno, halógeno, alquilo, o similares； R4A es cada uno independientemente hidrógeno, halógeno, alquilo, o similares； R4B es cada uno independientemente hidrógeno, halógeno, alquilo, o similares； R3A y R3B pu
