Abstract: A mitotic kinesin Eg5 inhibitor which comprises a thiadiazoline derivative represented by the general formula (I) or a pharmacologically acceptable salt thereof as an active ingredient: [wherein R1 represents a hydrogen atom and the like, R2 represents a hydrogen atom, —C(?W)R6 (wherein W represents an oxygen atom or a sulfur atom, and R6 represents substituted or unsubstituted lower alkyl and the like) and the like, R3 represents —C(?Z)R19 (wherein Z represents an oxygen atom or a sulfur atom, and R19 represents substituted or unsubstituted lower alkyl and the like) and the like, R4 represents substituted or unsubstituted lower alkyl and the like, and R5 represents substituted or unsubstituted aryl and the like] and the like are provided.

Abstract: A mitotic kinesin Eg5 inhibitor which comprises a thiadiazoline derivative represented by the general formula (I) or a pharmacologically acceptable salt thereof as an active ingredient: [wherein R1 represents a hydrogen atom and the like, R2 represents a hydrogen atom, —C(?W)R6 (wherein W represents an oxygen atom or a sulfur atom, and R6 represents substituted or unsubstituted lower alkyl and the like) and the like, R3 represents —C(?Z)R19 (wherein Z represents an oxygen atom or a sulfur atom, and R19 represents substituted or unsubstituted lower alkyl and the like) and the like, R4 represents substituted or unsubstituted lower alkyl and the like, and R5 represents substituted or unsubstituted aryl and the like] and the like are provided.

Abstract: (wherein R1 and R4 are the same or different and each represents a hydrogen atom, substituted or unsubstituted lower alkyl, substituted or unsubstituted lower alkynyl, substituted or unsubstituted lower alkenyl, or the like; R5 represents a substituted or unsubstituted heterocyclic group, substituted or unsubstituted aryl, or the like; R2 represents —C(?W)R6 or the like; R3 represents a hydrogen atom, —C(?WA)R6A, or the like) Antitumor agents which comprises a thiadiazoline derivative represented by the aforementioned general formula (I) or a pharmacologically acceptable salt thereof as an active ingredient are provided.

Abstract: A therapeutic and/or prophylactic agent for a solid tumor, which comprises a thiadiazoline derivative represented by the general formula (I), or a pharmaceutically acceptable salt thereof: [wherein, n represents an integer of 1 to 3, R1 represents a hydrogen atom, R2 represents lower alkyl, or R1 and R2 are combined together to represent alkylene, R3 represents lower alkyl, R4 represents NHSO2R6 (wherein R6 represents hydroxy or the like) or the like, and R5 represents aryl or the like] and the like are provided.

Abstract: A thiadiazoline derivative represented by the general formula (I), or a pharmacologically acceptable salt thereof: [wherein R1 represents a hydrogen atom and the like, R2 represents a hydrogen atom, —COR5 (wherein R5 represents lower alkyl and the like) and the like, R3 represents lower alkyl and the like, R4 represents aryl and the like, A represents —(CH2)n— (wherein n represents an integer of 1 to 6) and the like, and B represents —NR6R7 (wherein R6 and R7 are the same or different and represent a hydrogen atom, lower alkyl and the like) and the like] is provided.

Abstract: (wherein R1 and R4 are the same or different and each represents a hydrogen atom, substituted or unsubstituted lower alkyl, substituted or unsubstituted lower alkynyl, substituted or unsubstituted lower alkenyl, or the like; R5 represents a substituted or unsubstituted heterocyclic group, substituted or unsubstituted aryl, or the like; R2 represents —C(?W)R6 or the like; R3 represents a hydrogen atom, —C(?WA)R6A, or the like) Antitumor agents which comprises a thiadiazoline derivative represented by the aforementioned general formula (I) or a pharmacologically acceptable salt thereof as an active ingredient are provided.

Abstract: A mitotic kinesin Eg5 inhibitor which comprises a thiadiazoline derivative represented by the general formula (I) or a pharmacologically acceptable salt thereof as an active ingredient: [wherein R1 represents a hydrogen atom and the like, R2 represents a hydrogen atom, —C(?W)R6 (wherein W represents an oxygen atom or a sulfur atom, and R6 represents substituted or unsubstituted lower alkyl and the like) and the like, R3 represents —C(?Z)R19 (wherein Z represents an oxygen atom or a sulfur atom, and R19 represents substituted or unsubstituted lower alkyl and the like) and the like, R4 represents substituted or unsubstituted lower alkyl and the like, and R5 represents substituted or unsubstituted aryl and the like] and the like are provided.

Abstract: An antitumor agent comprising a thiadiazoline derivative represented by the general formula (I), or a pharmacologically acceptable salt thereof as an active ingredient: (wherein Z represents a sulfur atom and the like, R1 represents substituted or unsubstituted lower alkynyl and the like, R2 represents a hydrogen atom and the like, R3 represents substituted or unsubstituted lower alkyl and the like, and R4 represents substituted or unsubstituted aryl and the like), and the like are provided.

Abstract: (wherein R1 and R4 are the same or different and each represents a hydrogen atom, substituted or unsubstituted lower alkyl, substituted or unsubstituted lower alkynyl, substituted or unsubstituted lower alkenyl, or the like; R5 represents a substituted or unsubstituted heterocyclic group, substituted or unsubstituted aryl, or the like; R2 represents —C(?W)R6 or the like; R3 represents a hydrogen atom, —C(?WA)R6A, or the like) Antitumor agents which comprises a thiadiazoline derivative represented by the aforementioned general formula (I) or a pharmacologically acceptable salt thereof as an active ingredient are provided.

Abstract: Provided is steroid sulfatase inhibitors comprising, as the active ingredient, an estra-1,3,5(10)-triene derivative which is represented by formula (I): {wherein R1 and R2 are the same or different and represent a hydrogen atom, a lower alkyl group or, etc.; R3 represents a hydrogen atom etc.; R4 represents a hydrogen atom etc.; R5 represents a hydrogen atom etc.; R6 represents a cyano group, an amino group, COR53 (wherein R53 represents a substituted lower alkyl group etc.), a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, etc}, or pharmaceutically acceptable salts thereof.

Abstract: The present invention provides an aryl sulfamate derivative represented by Formula (I) 1

Abstract: Radicicol derivatives represented by the following formula (I) having tyrosine kinase inhibition activity or pharmacologically acceptable salts thereof: 1

Abstract: Provided is steroid sulfatase inhibitors comprising, as the active ingredient, an estra-1,3,5(10)-triene derivative which is represented by formula (I): 1

Abstract: Estra-1,3,5(10),16-tetraene derivatives represented by the following formula (I): (wherein R1 is as defined by the present specification.

Abstract: Radicicol derivatives represented by the following formula (I) having tyrosine kinase inhibition activity or pharmacologically acceptable salts thereof: wherein R1 and R2 are the same or different, and each represents hydrogen, alkanoyl, alkenoyl, tert-butyldiphenylsilyl or tert-butyldimethylsilyl; R3 represents Y—R5 {wherein Y represents substituted or unsubstituted alkylene; and R5 represents CONR5R7 (wherein R6 represents hydrogen, hydroxyl, substituted or unsubstituted lower alkyl, substituted or unsubstituted higher alkyl, and the like; R7 represents hydroxyl, substituted lower alkyl, and the like), CO2R12 (wherein R12 represents substituted lower alkyl, substituted or unsubstituted higher alkyl, and the like), and the like} and the like; X represents halogen or is combined together with R4 to represent a single bond; and R4 is combined together with X to represent a single bond, or represents hydrogen, alkanoyl, and the like.

Abstract: Estra-1,3,5(10),16-tetraene derivatives represented by the following formula (I): 1

Abstract: Radioicol derivatives represented by the following formula (I) having tyrosine kinase inhibition activity or pharmacologically acceptable salts thereof: wherein R1 and R2 are the same or different, and each represents hydrogen, alkanoyl, alkenoyl, tert-butyldiphenylsilyl or tert-butyldimethylsilyl; R3 represents Y—R5 (wherein Y represents substituted or unsubstituted alkylene; and R5 represents CONR6R7 (wherein R6 represents hydrogen, hydroxyl, substituted or unsubstituted lower alkyl, substituted or unsubstituted higher alkyl, and the like; R7 represents hydroxyl, substituted lower alkyl, and the like), CO2R12 (wherein R12 represents substituted lower alkyl, substituted or unsubstituted higher alkyl, and the like), and the like) and the like; X represents halogen or is combined together with R4 to represent a single bond; and R4 is combined together with X to represent a single bond, or represents hydrogen, alkanoyl, and the like.

Abstract: Radicicol derivatives represented by the following formula (I) having tyrosine kinase inhibition activity or pharmacologically acceptable salts thereof: 1

Abstract: Estra-1,3,5(10),16-tetraene derivatives represented by the following formula (I): (wherein R1 represents hydroxy, alkoxy, or NR2R3 (wherein R2 and R3 are the same or different, and each represents hydrogen, straight-chain lower alkyl having 1 to 3 carbon atoms, or branched-chain lower alkyl having 3 to 8 carbon atoms)), or pharmaceutically acceptable salts thereof.

Abstract: Radicicol derivatives represented by the following formula (I) having tyrosine kinase inhibition activity or pharmacologically acceptable salts thereof: wherein R1 and R2 are the same or different, and each represents hydrogen, alkanoyl, alkenoyl, tert-butyldiphenylsilyl or tert-butyldimethylsilyl; R3 represents Y—R5 {wherein Y represents substituted or unsubstituted alkylene; and R5 represents CONR6R7 (wherein R6 represents hydrogen, hydroxyl, substituted or unsubstituted lower alkyl, substituted or unsubstituted higher alkyl; R7 represents hydroxyl, substituted lower alkyl), CO2R12 (wherein R12 represents substituted lower alkyl, substituted or unsubstituted higher alkyl, X represents halogen.