These tricyclic compounds (1) can be used as therapeutic agents for neurodegenerative diseases. It is claimed that the compound and pharmaceutical ingredient are 1: a compound selected from formula (1) and its stereoisomer, acoustic isomer, corresponding isomer, tautometer and pharmaceutically acceptable salts, wherein: X1 is selected from O, s, s (o),X2 is selected from cr5r6, nr10 and ch10； X2 is selected from cr8r9 and O； X3 is selected from cr8r9 and O； X4 is selected from cr12r13 and N； X5 is selected from cr12r13 and O, where X2, X3 and X5 must contain C； R1 is selected from hydrogen, tar, aralquilo, heterogeneous and heterogeneous chemicals； R2 and R3 are selected, R4 is independently selected from hydrogen, halogen and tar, which contains hydrogen, hydrogen Xi, halogen, amino group, cyanogen, nitrogen, tar, alcoxi, acilo, aciloxi, alcoxicarbolo, sulfur, sulfur, sulfur, ariloxi, a thyroid gland and a heterocycle, including tar, alcoxi, acilo, aciloxi, alcoxicarbolo, sulfur, sulfuric acid, Sulphur,Alternative ariloxi, carbocyclo and heterocycle are replaced by hydrogen Xi, halogen, ammonia, cyanogen, nitrogen, oxo, alternative asphalt, alternative alcoxi, sulfonate, acid, oxycarbide, halotar or optional replacement carbocyclo； R5 and R6 are selected from hydrogen and hydrogen Xi respectively, Halogen, amino, cyanogen, nitrogen, hydrocarbon, alcox, acilo, aciloxi, alcoxin, sulfur, sulfur, sulfur, sulfonyl, ariloxi, a thyroid and a heterocycle, in which tar, alcoxi, acilo, aciloxi, alcoxim, sulfonyl, sulfur, sulfonamide, acylamino, ariloxi, carbocycle and heterocycle can be replaced. Aminocyano, nitro, oxo, optionally substituted alkyl, optionally substituted alkoxy, sulfanyl, acyl, alkoxycarbonyl, haloalkyl or optionally substituted carbocycle, or R5 and R6 taken together form an oxo group, or R5 and R6 together with the atom to which they are attached form a carbocycle or heterocycle； R7 is selected from hydrogen, alkyl, alkoxy, acyl, acyloxy, alkoxycarbonyl,
