Tanshinone derivatives: a patent review (January 2006 - September 2012).

INTRODUCTION: Tanshinone IIA (TSIIA), cryptotanshinone and tanshinone I are major bioactive constituents of Danshen, a Chinese herbal medicine. Sodium tanshinone IIA sulfonate (STS) is a water-soluble derivative of TSIIA and it is currently used for treating cardiovascular diseases in China. AREAS COVERED: The article presents a review of the anti-atherosclerosis, cardioprotective effects, neuroprotection and anti-tumor activities of TSIIA and a review of patents on tanshinone derivatives from January 2006 to September 2012. EXPERT OPINION: Mechanistic studies have discovered that TSIIA modulates ion channels, kinases, hormone receptors, apoptosis proteins, growth factors, cytokines, microRNA, tumor suppressor and many other targets, revealing an intricate biological network modulated by TSIIA. Many patents have attempted to overcome the low water solubility of TSIIA and tanshinone I by attaching a polar substituent or by a prodrug strategy. However, biological activities of these tanshinone derivatives need to be further evaluated. Given the extensive in vitro and in vivo biological activities of TSIIA, this compound is a promising candidate to be further developed as a novel therapeutics for treating atherosclerosis, cardiovascular diseases, neurodegenerative diseases and cancer.