10.22376/ijpbs.2019.10.1.p1-12 Volume 5 Issue 3 2014 (July- September) 3D QSAR viz. 3 descriptor quantitative structure and activity relationship studies for a series of compounds i.e. Schiff base derivatives using their semi-empirical quantum chemical descriptors and their laboratory reported activities against pathogen viz. . lessThan i greaterThan Ralstonia solanaecearum lessThan /i greaterThan (ITCC NO –B1- 0002 ) have been carried out and reported in the present paper. Graphs between observed and predicted activities, both in the terms of p(MIC) lessThan i greaterThan cal lessThan /i greaterThan and p(MIC) lessThan i greaterThan obs. lessThan /i greaterThan are also being reported on the basis of which this may be concluded that some parameters/descriptors have a positive contribution towards the activity. The method has been proved to be useful tool for such type of studies. KISHOR ARORA Semiempirical/3D-qsar/Schiff bases compounds 402-421