which also has brief biography of her. The song also appears in Atul's blog, where Arunkumar Deshmukh comments that the singer may be Suprabha Ghosh/Sarkar. She did sing in earlier films
http://www.youtube.com/watch?v=PEcxCzaOPLE (1937). Apparently, she was a talented dancer, choreographer and produced ballets. From a 1981 article (via)by Debu Mazumdar “For men of my generation Sadhana Bose was as great a dancer as the woman she was — a living legend and the ‘toast of India’s gilded youth,’ so to say. She was a remarkably beautiful woman, a highly talented dancer and musician and a top-notch glamour girl of the screen. She was a trend-setter in the world of fashion, (the shimmering satin sari and glossy red lipstick, for example) in the same way as the legendary Harlow was in Hollywood those days.”"
Her best known film seems to be Raj Nartaki (1941) and both Richard and Memsaab wrote about it. Shovana Narayan who started learning kathak from Sadhona Bose writes about here here.