Synthesis of 3-amino-4-substituted pyrazole derivatives

A process of making a 3-amino-4-substituted pyrazole derivative of the formula:

• in which
• R2 is selected from the group consisting of R9, alkyl, alkenyl, alkynyl, CF3, heterocyclyl, heterocyclylalkyl, halogen, haloalkyl, aryl, arylalkyl, heteroarylalkyl, alkynylalkyl, cycloalkyl, heteroaryl, alkyl substituted with 1-6 R9 groups which can be the same or different and are independently selected from the list of R9 shown below, aryl substituted with 1-3 aryl or heteroaryl groups which can be the same or different and are independently selected from phenyl, pyridyl, thiophenyl, furanyl and thiazolo groups, aryl fused with an aryl or heteroaryl group, heteroaryl substituted with 1-3 aryl or heteroaryl groups which can be the same or different and are independently selected from phenyl, pyridyl, thiophenyl, furanyl and thiazolo groups, heteroaryl fused with an aryl or heteroaryl group,
• wherein one or more of the aryl and/or one or more of the heteroaryl in the above-noted definitions for R2 can be unsubstituted or optionally substituted with one or more moieties which can be the same or different, each moiety being independently selected from the group consisting of halogen, —CN, —OR5, —SR5, —S(O2)R6, —S(O2)NR5R6, —NR5R6, —C(O)NR5R6, CF3, alkyl, aryl and OCF3;
• R4 is H, halo or alkyl;
• R5 is H, alkyl, aryl or cycloalkyl;
• R6 is selected from the group consisting of H, alkyl, alkenyl, aryl, arylalkyl, arylalkenyl, cycloalkyl, heterocyclyl, heterocyclylalkyl, heteroaryl, and heteroarylalkyl, wherein each of said alkyl, aryl, arylalkyl, cycloalkyl, heterocyclyl, heterocyclylalkyl, heteroaryl, and heteroarylalkyl can be unsubstituted or optionally substituted with one or more moieties which can be the same or different, each moiety being independently selected from the group consisting of halogen, alkyl, aryl, cycloalkyl, heterocyclylalkyl, CF3, OCF3, CN, —OR5, —NR5R10, —C(R4R5)p—R9, —N(R5)Boc, —(CR4R5)pOR5, —C(O2)R5, —C(O)R5, —C(O)NR5R10, —SO3H, —SR10, —S(O2)R7, —S(O2)NR5R10, —N(R5)S(O2)R7, —N(R5)C(O)R7 and —N(R5)C(O)NR5R10;
• R7 is selected from the group consisting of alkyl, cycloalkyl, aryl, arylalkenyl, heteroaryl, arylalkyl, heteroarylalkyl, heteroarylalkenyl, and heterocyclyl, wherein each of said alkyl, cycloalkyl, heteroarylalkyl, aryl, heteroaryl and arylalkyl can be unsubstituted or optionally independently substituted with one or more moieties which can be the same or different, each moiety being independently selected from the group consisting of halogen, alkyl, aryl, cycloalkyl, CF3, OCF3, CN, —OR5, —NR5R10, —CH2OR5, —C(O2)R5, —C(O)NR5R10, —C(O)R5, —SR10, —S(O2)R10, —S(O2) NR5R10, —N(R5)S(O2)R10, —N(R5)C(O)R10 and —N(R5)C(O)NR5R10;
• R8 is selected from the group consisting of R6, —OR6, —C(O)NR5R10, —S(O2)NR5R10, —C(O)R7, —C(═N—CN)—NH2, —C(═NH)—NHR5, heterocyclyl, and —S(O2)R7;
• R9 is selected from the group consisting of halogen, —CN, —NR5R10, —C(O2)R6, —C(O)NR5R10, —OR6, —SR6, —S(O2)R7, —S(O2)NR5R10, —N(R5)S(O2)R7, —N(R5)C(O)R7 and —N(R5)C(O)NR5R10;
• R10 is selected from the group consisting of H, alkyl, aryl, arylalkyl, cycloalkyl, heterocyclyl, heterocyclylalkyl, heteroaryl, and heteroarylalkyl, wherein each of said alkyl, aryl, arylalkyl, cycloalkyl, heterocyclyl, heterocyclylalkyl, heteroaryl, and heteroarylalkyl can be unsubstituted or optionally substituted with one or more moieties which can be the same or different, each moiety being independently selected from the group consisting of halogen, alkyl, aryl, cycloalkyl, heterocyclylalkyl, CF3, OCF3, CN, —OR5, —NR4R5, —C(R4R5)p—R9, —N(R5)Boc, —(CR4R5)pOR5, —C(O2)R5, —C(O)NR4R5, —C(O)R5, —SO3H, —SR5, —S(O2)R7, —S(O2)NR4R5, —N(R5)S(O2)R7, —N(R5)C(O)R7 and —N(R5)C(O)NR4R5;
• or optionally (i) R5 and R10 in the moiety —NR5R10, or (ii) R5 and R6 in the moiety —NR5R6, may be joined together to form a cycloalkyl or heterocyclyl moiety, with each of said cycloalkyl or heterocyclyl moiety being unsubstituted or optionally independently being substituted with one or more R9 groups;
• and
• m is 0 to 4
• which comprises:
• (a) reacting a compound of formula II
• with a compound of formula III
• where R′ is alkyl, substituted alkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, aralkyl, substituted aralkyl, alkylaryl, substituted alkylaryl, cycloalkyl, substituted cycloalkyl, heterocycyl or substituted heterocycyl,
• in the presence of LDA, LiHMDS, KHMDS, or NaHMDS and a solvent at a temperature between about −100° C. to about 0° C. to give a compound of formula IV
• and
• b) reacting a compound of formula IV with hydrazine and acetic acid in an alcoholic solvent at a temperature between about 50° C. to about 150° C. to give a compound of formula I.