Abstract: This invention relates to novel compounds of general formula (I) ##STR1## wherein R.sup.1 represents an organic group, R.sup.2 represents a hydrogen atom or an organic group, and the asterisk denotes that the group R.sup.1 is predominantly in the R- or S-configuration such that the compound is in substantially enantiomerically pure form. The compounds are a useful source of chiral nucleophiles, e.g. undergoing stereoselective Michael addition to .alpha.,.beta.-unsaturated carboxylic acid derivatives.

Abstract: The present invention relates to the synthesis of chiral amino acids and to novel ferrocene-substituted oxazolidinone derivatives useful in such syntheses.

Abstract: This invention relates to novel compounds of general formula (I): ##STR1## wherein the two R.sup.1 groups are identical lower alkyl groups or together form a lower alkylene group; R.sup.2 and R.sup.3 are both different and are selected from hydrogen atoms or organic groups; X and X', which may be the same or different, are selected from O, S and NR, where R represents an organic group; and the asterisk denotes that the configurations of R.sup.2 and R.sup.3 are such that the compound (I) is in substantially enantiomerically pure 4R- or 4S-form. The compounds are useful chiral auxiliaries to which a wide range of, for example, acyl groups containing prochiral centers may be readily and reversibly coupled to the 3-position amino group.