Abstract: Disclosed are a heterocyclic compound for an immune checkpoint inhibitor capable of blocking a VISTA signaling pathway, and a preparation method therefor and a use thereof. The compound is as represented by formula I. The compound has a novel structure, can be formulated for oral administration, overcomes the treatment defects and drug resistance of monoclonal antibody-based immune checkpoint inhibitors, can be used to prepare a small molecule inhibitor easily, and is convenient for industrial production.

Abstract: A heterocyclic urea compound, and specifically discloses an indoleamine-2,3-dioxygenase inhibitor of a heterocyclic urea compound, which solves the problems of weak curative effect and larger toxic and side effects of existing immunological therapy drugs. The invention further provides a preparation method for an indoleamine-2,3-dioxygenase inhibitor of a heterocyclic urea compound, and an application of the indoleamine-2,3-dioxygenase inhibitor of a heterocyclic urea compound or a pharmaceutically acceptable salt thereof in preparing drugs for treating or preventing tumors.

Abstract: A heterocyclic urea compound, and specifically discloses an indoleamine-2,3-dioxygenase inhibitor of a heterocyclic urea compound, which solves the problems of weak curative effect and larger toxic and side effects of existing immunological therapy drugs. The invention further provides a preparation method for an indoleamine-2,3-dioxygenase inhibitor of a heterocyclic urea compound, and an application of the indoleamine-2,3-dioxygenase inhibitor of a heterocyclic urea compound or a pharmaceutically acceptable salt thereof in preparing drugs for treating or preventing tumors.

Abstract: The present invention relates to a cyclic peptide compound, and a preparation method, pharmaceutical composition and use thereof. In particular, the cyclic peptide compound of the present invention has a structure as shown by general formula (I). The compound of general formula (I), and isomers, racemates, pharmaceutically acceptable salts, crystalline hydrates, solvates or mixtures thereof have a use in the preparation of medicaments for preventing or treating mammalian diseases associated with histone deacetylase dysregulations.

Abstract: The present invention relates to a cyclic peptide compound, and a preparation method, pharmaceutical composition and use thereof. In particular, the cyclic peptide compound of the present invention has a structure as shown by general formula (I). The compound of general formula (I), and isomers, racemates, pharmaceutically acceptable salts, crystalline hydrates, solvates or mixtures thereof have a use in the preparation of medicaments for preventing or treating mammalian diseases associated with histone deacetylase dysregulations.