Abstract: Devices and processes for synthesizing, purifying and analyzing large numbers of compounds for use in combinatorial libraries, are disclosed. The processes involve generating a series of compounds in multi-well plates or multi-tube racks, purifying the reaction mixtures, analyzing the purified compounds, and optionally performing bioassays on the compounds. The information regarding the compounds is stored in a central database. The devices include one or more multi-tube arrays, a purification device, means for transferring the contents of the tubes, a solvent evaporator, analytical instrumentation, and, optionally, a weighing instrument. The multi-tube array(s) optionally include a cover, which can be placed on or removed from the array by computer control. By correlating the orientation of tubes from one stage to the next, it is possible to use a single bar code or other identifying mark for each multi-tube array rather than for each individual tube.