Abstract: A process for the production of a compound of formula (I) ##STR1## which comprises cultivating a microorganism of the genus Streptomyces capable of producing the compound of formula (I) in the presence of one or more fatty acids and/or salts, esters and amides of these acids, whereby the compound of formula (I) is produced, and if desired isolating the said compound. The fatty acid increases the yield of the formula (I) compound and is preferably isobutyric or valeric acid.

Abstract: Compounds of formula (1) ##STR1## wherein R represents a sugar residue or an acylated derivative thereof;R.sup.1 represents a methyl, ethyl or isopropyl group;Y.sup.1 is --CH.sub.2, Y.sup.2 is --CH-- and X represents ##STR2## [wherein R.sup.2 represents a hydrogen atom or a group OR.sup.6 (where OR.sup.6 is a hydroxyl group or a substituted hydroxyl group having up to 25 carbon atoms) and R.sup.3 represents a hydrogen atom, or R.sup.2 and R.sup.3 together with the carbon atom to which they are attached represent >C.dbd.0, >C.dbd.CH.sub.2 or >C.dbd.NOR.sup.7 (where R.sup.7 represents a hydrogen atom, a C.sub.1-8 alkyl group or a C.sub.3-8 alkenyl group) and the group >C.dbd.NOR.sup.7 is in the E configuration] or --Y.sup.1 --X--Y.sup.2 -- represents --CH.dbd.CH--CH-- or --CH.sub.2 --CH.dbd.C--; andR.sup.4 represents a group OR.sup.6 as defined above and R.sup.5 represents a hydrogen atom, or R.sup.4 and R.sup.5 together with the carbon atom to which the are attached represent >C.dbd.0 or >C.

Abstract: Compounds of formula (1) ##STR1## and their salts, wherein R.sup.1 is a methyl, ethyl or isopropyl group each substituted by a hydroxyl group or R.sup.1 is a group --(CH.sub.2).sub.n R7 or a group --CH(CH.sub.3)R.sup.7 (where n is zero or 1 and R.sup.7 l is CHO or CO.sub.2 H);Y.sup.1 is --CH.sub.2 --, Y.sup.2 is --CH-- and X represents ##STR2## [where R.sup.2 is a hydrogen atom or a group OR.sup.8 is a hydroxyl group or a substituted hydroxyl group having up to 25 carbon atoms) and R.sup.3 is a hydrogen atom, or R.sup.2 and R.sup.3 together with the carbon atom to which they are attached represent >.dbd.O, >C.dbd.CH.sub.2 or >C.dbd.NOR.sup.9 (where R.sup.9 is a hydrogen atom or a C.sub.1-8 alkyl or C.sub.3-8 alkenyl group) and the group >C.dbd.NOR.sup.9 is in the E configuration] or --Y.sup.1 --X--Y.sup.2 -- represents --CH.dbd.CH--CH-- or --CH.sub.2 --CH.dbd.C--;R.sup.4 is a group OR.sup.8 as defined above and R.sup.5 is a hydrogen atom, or R.sup.4 and R.sup.

Abstract: Compounds of formula (1) ##STR1## and salts thereof, wherein R.sup.1 represents a methyl, ethyl or isopropyl group;Y.sup.1 is --CH.sub.2 --, Y.sup.2 is --CH-- and X represents ##STR2## where R.sup.2 represents a hydrogen atom or a group OR.sup.8 (where OR.sup.8 is a hydroxyl group or a substituted hydroxyl group having up to 25 carbon atoms) and R.sup.3 represents a hydrogen atom, or R.sup.2 and R.sup.3 together with the carbon atom to which they are attached represent >C.dbd.O, >C.dbd.CH.sub.2 or >C.dbd.NOR.sup.9 (where R.sup.9 represents a hydrogen atom, a C.sub.1-8 alkyl group or a C.sub.3-8 alkenyl group) and the group >C.dbd.NOR.sup.9 is in the E configuration] or --Y.sup.1 --X--Y.sup.2 -- represents --CH.dbd.CH--CH-- or --CH.sub.2 --CH.dbd.C--;R.sup.4 represents a group OR.sup.8 as defined above and R.sup.5 represents a hydrogen atom, or R.sup.4 and R.sup.5 together with the carbon atom to which they are attached represent >C.dbd.O or >C.dbd.NOR.sup.9a (where R.sup.