Our Location. Our Location s. Drs. Thompson, Goldberg, Donka, and Manthous. 22 West Main St. Niantic, Connecticut 06357. Location Hours: Appointments Mon thru Fri 9:00 to 6:00 Office opens daily at 8:00 am Doctors days off: Dr. Thompson Mon and Wed afternoon Dr. Goldberg Wed afternoon Dr. Donka Tues Dr. Manthous Wed and Thurs. Phone: 860-739-4431..