Hello shri darshini ,
1. Christian medical college ,vellore.
2. Shri rama chandra medical college and research institute, chennai.
3. SRM Medical college and Hospital.
4. PSG institute of medical sciences.
5. Saveetha institute of medical and technical sciences.
You can  refer the link below for knowing their ranking as well :-
https://medicine.careers360.com/colleges/ranking/top-private-medical-colleges-in-tamil-nadu?page=1
I hope the above information is useful to you,
All the best!