To obtain the subject polyhydro derivative, composed of a 13-hydroxy- dihydro and tetrahydro derivative of tyrosine, derived from a 16-membered macrolide showing an antimicrobial activity, and composed of a semisynthetic antibiotic useful as an antimicrobial agent or the like.

This compound is composed of a new 13-hydroxy-dihydro and tetrahydro derivative of tyrosine, shown by formula I (R is O or NOH; R1 is CHO, CH(OCH3)2 or CH=NOH; R2 is a mycarosyl shown by formula II or H; and the broken line represents a double or single bond), and is useful as an antimicrobial agent or the like composed of a semisynthetic antibiotic derived from a group of 16-membered macrolides showing an antimicrobial activity. One of the methods to produce the compound reduces a compound shown by formula III with powdered Zn, and converts the reaction product with O as R, CHO or CH(OCH3)2 as R1, a micarosyl or H as R2, and a double bond as the broken line into an oxime.