1. A method of preparing a 7-, 8-, 9- or 10-substituted tetracycline compound, combining a reactive tetracycline-based precursor compound and a reactive organic substituent precursor in the presence of a transition metal catalyst under conditions such that a tetracycline compound substituted with said organic substituent is formed. 2. The method of claim 1, wherein said transition metal catalyst comprises an organopalladium catalyst. 3. The method of claim 2, wherein said organopalladium catalys...