MarvinSketch & MarvinViewFree structure/reaction drawing editor from ChemAxon. Structure editor supporting multiple file formats, for Windows, Mac and Linux. Marvin JS is one of the editor options in Reaxys, along with ChemDraw JS.
Free access is for personal, non-commercial use only. Prompted to renew every 2 months. Registration required. Under your account info, you'll find a alphanumeric license key and an offline license for downloading. You can use either option to activate your Marvin license once installed.