Anti-penicillin resistant pneumococci agent and novel 16-membered macrolide derivative

A method for treatment of penicillin-resistant pneumococcal infection, which comprises administrating a pharmaceutically effective amount of a compound represented by the formula (I) or a pharmacologically acceptable salt thereof to a subject having penicillin-resistant pneumococcal infection:

• wherein, in the formula (I), R represents any one of a halogen atom, an azido group, Ra-Wa-, Rb-Wb-, Rc-Wc-, and RdRd′N—;
• the Wa represents one of —CO—O— and —CO—NH—;
• the Ra represents any one of a hydrogen atom, and a C1-12 alkyl group, an unsaturated C2-12 alkyl group, a C6-14 aryl group, a 5- to 14-membered ring heteroaryl group, a C7-16 aralkyl group, a 5- to 14-membered ring heteroaralkyl group, a C1-12 alkoxy group, an unsaturated C2-12 alkoxy group, a C6-14 aryloxy group and a 5- to 14-membered ring heteroaryloxy group, which may each have a substituent;
• the Wb represents —O—;
• the Rb represents any one of a C1-12 alkyl group, an unsaturated C2-12 alkyl group, a C6-14 aryl group, a 5- to 14-membered ring heteroaryl group, a C7-16 aralkyl group, and a 5- to 14-membered ring heteroaralkyl group, which may each have a substituent;
• the Wc represents any one of —NH—CO—O—, —NH—CO—NH—, —NH—CS—NH—, and —S—;
• the Rc represents any one of a hydrogen atom, and a C1-12 alkyl group, an unsaturated C2-12 alkyl group, a C6-14 aryl group, a 5- to 14-membered ring heteroaryl group, a C7-16 aralkyl group and a 5- to 14-membered ring heteroaralkyl group, which may each have a substituent;
• and the Rd and the Rd′ may be the same or different and represent any one of a hydrogen atom, and a C1-12 alkyl group, an unsaturated C2-12 alkyl group, a C6-14 aryl group, a 5- to 14-membered ring heteroaryl group, a C7-16 aralkyl group, a 5- to 14-membered ring heteroaralkyl group, and a 3- to 8-membered ring nonaromatic heterocyclic group which the Rd and the Rd′ together form, each of which groups may have a substituent.