Hepatitis B antiviral agents

A compound represented by Formula (I):

• or a pharmaceutically acceptable salt thereof, wherein:
• A is selected from the groups below by removal of one hydrogen atom,
• wherein each group is optionally substituted and is connected to the dihydropypyrimidine core through a carbon atom;
• B is selected from the group consisting of hydrogen, CN, optionally substituted —C1-C6 alkyl, and optionally substituted —C3-C6 cycloalkyl;
• X is optionally substituted phenyl;
• Y is
• which is optionally substituted;
• Z is hydrogen or —CH2M;
• wherein M is hydrogen, —CN, —NO2, —OR1, protected hydroxy, —CR′R1aR2a, —NR1R2, protected amino, —CO2R1, or —C(O)NR1R2;
• R′ is selected from the group consisting of hydrogen, optionally substituted —C1-C8 alkyl, optionally substituted —C2-C8 alkenyl, optionally substituted —C2-C8 alkynyl, optionally substituted —C3-C8 cycloalkyl, —CN, —OR1, and —NR1R2;
• R1a and R2a are independently selected from the group consisting of hydrogen, optionally substituted —C1-C8 alkyl, optionally substituted —C2-C8 alkenyl, optionally substituted —C2-C8 alkynyl, optionally substituted —C3-C8 cycloalkyl, optionally substituted 3- to 8-membered heterocyclic, optionally substituted aryl and optionally substituted heteroaryl;
• alternatively, R1a and R2a are taken together with the carbon atom to which they are attached to form an optionally substituted C3-C10-cycloalkyl or an optionally substituted 3 to 10-membered heterocyclic;
• R1 and R2 at each occurrence are independently selected from the group consisting of hydrogen, optionally substituted —C1-C8 alkyl, optionally substituted —C2-C8 alkenyl, optionally substituted —C2-C8 alkynyl, optionally substituted —C3-C8 cycloalkyl, optionally substituted 3- to 8-membered heterocyclic, optionally substituted aryl and optionally substituted heteroaryl;
• alternatively, R1 and R2 are taken together with the atom to which they are attached to form an optionally substituted 3- to 10-membered heterocyclic;
• and
• R3 at each occurrence is selected from the group consisting of optionally substituted —C1-C8 alkyl, optionally substituted —C2-C8 alkenyl, optionally substituted —C2-C8 alkynyl, optionally substituted —C3-C8 cycloalkyl, optionally substituted 3- to 8-membered heterocyclic, optionally substituted aryl and optionally substituted heteroaryl.