Process for preparing sulfonamide compounds

A process for preparing a compound of formula (I):

• or a pharmaceutically acceptable salt thereof, wherein R1 is —SO2R′;
• R′ is alkyl;
• R2 is alkyl;
• R3 is alkyl;
• R4 is halogen;
• R5 is halogen;
• R6 is H, halogen, or alkyl;
• Y is
• Q is —C(═O)O(C1-5 alkylene);
• Rb is hydrogen or alkyl;
• and n, r and s each independently are 1, 2, 3, 4, 5, or 6;
• wherein the process comprises one or more of the following steps:
• 1) converting a compound of formula 1:
• to form a compound of formula 2:
• 2) reacting the compound of formula 2 with a compound of formula 3:
• wherein R7 is alkyl, and m is 1, 2, 3, 4, or 5;
• to form a compound of formula 4:
• 3) converting the compound of formula 4 to form a compound of formula 5:
• 4) converting the compound of formula 5 to form the compound of formula (I);
• and
• wherein the compound of formula 1 is prepared by a method comprising one or more of the following steps:
• 1′) reacting a compound of formula 1′:
• with a compound of formula 2′:
• to form a compound of formula 3′:
• 2′) reacting the compound of formula 3′ with a compound of formula 4′:
• to form a compound of formula 5′:
• 3″) reacting the compound of formula 5′ with a compound of formula 6′:
• to form a compound of formula 7′,
• 4′) converting the compound of formula 7′ to form a compound of formula 8′:
• 5′) converting the compound of formula 8′ to form a compound of formula 9′:
• 6′) converting the compound of formula 9′ to form a compound of formula 10′:
• 7′) converting the compound of formula 10′ to form a compound of formula 11′:
• 8′) reacting the compound of formula 11′ with a compound of formula 12′:
• to form a compound of formula 13′:
• 9′) converting the compound of formula 13′ to form a compound of formula 14′,
• 10′) reacting the compound of formula 14′ with a compound of formula 15′:
• to form a compound of formula 16′:
• and
• 11′) reacting the compound of formula 16′ with a compound of formula 17′:
• to form a compound of formula 1.