Heteroaryloxy quinazoline derivative

A compound represented by a formula (I):

• wherein the A ring represents a 5- or 6-membered heteroaryl ring that is selected from the group consisting of:
• pyrazolyl, pyrazinyl, thiadiazolyl, thiazolyl, pyridinyl, thiatriazolyl, triazolyl, tetrazolyl, imidazolyl, pyrimidinyl, pyridazinyl, triazinyl, oxazolyl, oxadiazolyl and isoxazolyl groups, which may have one or two groups selected from the group consisting of lower alkyl, lower alkoxy, halogen, hydroxy, C3-7 cycloalkyl and lower alkyl having 1-3 identical or different lower alkoxy groups, halogen atoms or hydroxy groups, or represents a ring in which the 5- or 6-membered heteroaryl ring and a benzene or pyridine ring are condensed;
• ring B represents a 5- or 6-membered heteroaryl group having 1-3 identical or different hetero atoms selected from the group consisting of nitrogen, sulfur and oxygen atoms;
• R represents a group selected from the group consisting of lower alkyl, lower alkoxy, halogen, hydroxy and lower alkyl having 1-3 identical or different lower alkoxy groups, halogen atoms or hydroxy groups;
• k represents an integer of from 0 to 3;
• R1 denotes a group represented by a formula (II-1), (II-2), (II-3) or II-4):
• wherein R11 and R12 each independently represent hydrogen, lower alkyl or C3-7 cycloalkyl, or R11 and R12, together with the nitrogen atom to which they are bound, constitute 4- to 7-membered nitrogen-containing aliphatic rings (which may be substituted with 1-3 identical or different halogen atoms), or any carbon atom of (CH2)m, together with R11 or R12, may constitute 4- to 7-membered nitrogen-containing aliphatic rings;
• any carbon atom in (CH2)m may be substituted with a lower alkyl group;
• the nitrogen atom to which R11 and R12 are bound may form N-oxide;
• and
• m represents an integer of from 2 to 6,
• a group represented by a formula (II-2)
• —O—(CH2)n—R13 (II-2)
• wherein:
• R13 represents lower alkoxy, hydroxy or carboxyl;
• n represents an integer of from 1 to 6;
• upon R13 being lower alkoxy, the lower alkoxy, together with any carbon atom of (CH2)n, may form 5- to 7-membered aliphatic rings;
• and any carbon atom in (CH2)n may be substituted with a lower alkyl group),
• a group represented by a formula (II-3)
• wherein R14 and R15 are synonymous with the above R11 and R12;
• p represents an integer of from 2 to 6;
• and
• R3 represents a hydrogen atom or a lower alkyl group), or a group represented by a formula (II-4)
• wherein:
• R16 and R17 are synonymous with the above R11 and R12;
• q represents an integer of from 2 to 6;
• and
• R4 represents a hydrogen atom or a lower alkyl group,
• R2 is a group selected from the group consisting of:
• lower alkyl, lower alkoxy, halogen, hydroxy, cyano, carboxyl, alkoxycarbonyl, N-alkylcarbamoyl, N,N-dialkylcarbamoyl, lower alkylsulfonyl and lower alkyl having 1-3 identical or different lower alkoxy groups, halogen atoms, hydroxy groups, cyano groups, carboxyl groups, alkoxycarbonyl groups, N-alkylcarbamoyl groups, N,N-dialkylcarbamoyl groups or lower alkylsulfonyl groups, and
• r represents an integer of from 0 to 3,
• or a pharmaceutically acceptable salt thereof.