Novel racemic rhazinilam analogues 2 by modification of the D-ring size and the substituents on the juncture of B and D rings have been first prepared in our laboratory from chloroaldehydes 3 and indoloazepine 4 in 6-8 steps. SAR and X-ray structure analysis of three different D-ring size rhazinilam analogues are reported. Among analogues prepared so far, we have observed that reducing or increasing the size of ring D results in loss of activity in terms of the apparent interaction of rhazinilam with tubulin; replacing the ethyl group with a bulkier substituent has unpredictable results. Some of analogues have no change or even enhanced activity compared with rhazinilam.