Oxazine compound, composition and cured product

An oxazine compound comprising:

• a structure which is represented by General Formula (1-1):
• wherein, in General Formula (1-1),
• Ar1 represents a substituted or unsubstituted aromatic group,
• a ring A represents a substituted or unsubstituted aromatic ring,
• each R1 is indenpendtly a functional group represented by General Formula (2)
• a1-X1—Y1—X2—≡—R2 (2),
• and R3 and R4 each independently represent a hydrogen atom, or an alkyl group having 1 to 3 carbon atoms;
• and wherein, in General Formula (2),
• X1, X2, and Y1 each independtly represent a single bond or a divalent linking group,
• R2 represents a hydrogen atom, a hydrocarbon group, or a hydrocarbon group in which one or more hydrogen atoms contained in the hydrocarbon group are substituted with any one of a hydroxyl group, an alkoxy group, and a halogen atom,
• and a1 represents a bonding point to the oxazinc compound (1-1);
• and wherein the divalent linking group in each of X1, X2, and Y1 in General Formula (2) is an oxygen atom;
• a divalent hydrocarbon group;
• a divalent group in which one or more hydrogen atoms contained in a divalent hydrocarbon group are substituted with a hydroxyl group, an alkoxy group, or a halogen atom;
• a carbonyl group;
• an ester group;
• an amide group;
• an imino group;
• an azo group;
• a sulfide group;
• a sulfone group;
• or a divalent linking group formed by combining two or more these groups.