They are also not related to letter ‘d’ and ‘l’ (see Unit 6) The meaning
of D– and L– notations is as follows The letters ‘D’ or ‘L’ before the name of any compound indicate the
relative configuration of a particular stereoisomer of a compound with
respect to configuration of some other compound, configuration of
which is known In the case of carbohydrates, this refers to their
relation with a particular isomer of glyceraldehyde