can I get job in drug companies like Cipla ,Dr Reddy etc after doing an msc in normal chemistry
Yes you can depending on the openings, though there are lower number of vacancies for M.Sc. Graduates. Most of the Companies like Cipla , Dr Reddy look for Doctorates in Chemistry, Pharmaceutical and Chemical or perhaps BioChemical and BioTechnology Engineering graduates nowadays.
You have many job options after a MSc in Chemistry though, you can join a Public Research Organization like BARC or DRDO, which have annual openings each year for Chemistry Graduates, or perhaps a CSIR Lab like NML Jamshedpur or National Chemical Laboratory, Pune as a Trainee Scientist of Project Associate. PSUs like IOCL and ONGC also have openings through GATE for M.Sc. Chemistry Graduates. Many after masters also pursue a doctoral degree in Chemistry, while many move to Academic Institutions and Eminent Coaching Institutes for Teaching Purposes.
