Stereospecific Inhibitory Effects of CCG-1423 on the Cellular Events Mediated by Myocardin-Related Transcription Factor A.

CCG-1423 suppresses several pathological processes including cancer cell migration, tissue fibrosis, and the development of atherosclerotic lesions. These suppressions are caused by inhibition of myocardin-related transcription factor A (MRTF-A), which is a critical factor for epithelial-mesenchymal transition (EMT). CCG-1423 can therefore be a potent inhibitor for EMT. CCG-1423 and related compounds, CCG-100602 and CCG-203971 possess similar biological activities. Although these compounds are comprised of two stereoisomers, the differences in their biological activities remain to be assessed. To address this issue, we stereoselectively synthesized optically pure isomers of these compounds and validated their biological activities. The S-isomer of CCG-1423 rather than the R-isomer exhibited modestly but significantly higher inhibitory effects on the cellular events triggered by MRTF-A activation including serum response factor-mediated gene expression and cell migration of fibroblasts and B16F10 melanoma cells. Accordingly, the S-isomer of CCG-1423 more potently blocked the serum-induced nuclear import of MRTF-A than the R-isomer. No such difference was observed in cells treated with each of two stereoisomers of CCG-100602 or CCG-203971. We previously reported that the N-terminal basic domain (NB), which functions as a nuclear localization signal of MRTF-A, is a binding site for CCG-1423. Consistent with the biological activities of two stereoisomers of CCG-1423, docking simulation demonstrated that the S-isomer of CCG-1423 was more likely to bind to NB than the R-isomer. This is a first report demonstrating the stereospecific biological activities of CCG-1423.

[Chapter 2. Transitions in drug-discovery technology and drug-development in Japan (1980-2010)].

In 1970s, the material patent system was introduced in Japan. Since then, many Japanese pharmaceutical companies have endeavored to create original in-house products. From 1980s, many of the innovative products were small molecular drugs and were developed using powerful medicinal-chemical technologies. Among them were antibiotics and effective remedies for the digestive organs and circulatory organs. During this period, Japanese companies were able to launch some blockbuster drugs. At the same time, the pharmaceutical market, which had grown rapidly for two decades, was beginning to level off. From the late 1990s, drug development was slowing down due to the lack of expertise in biotechnology such as genetic engineering. In response to the circumstances, the research and development on biotechnology-based drugs such as antibody drugs have become more dynamic and popular at companies than small molecule drugs. In this paper, the writers reviewed in detail the transitions in drug discovery and development between 1980 and 2010.

[Chapter 4. Transitions in pharmaceutical market, production and sales in Japan (1980-2010)].

In this paper, the writers reviewed in detail the pharmaceutical market and the shifts in manufacturing and sales including the trade balance in Japan over a thirty-year period from 1980 to 2010. From the 1980s to the 1990s, many innovative pharmaceutical products were developed and launched in the Japanese market. During the same period, some Japanese companies managed to develop their first internationally marketable drugs, which were antibiotics and effective remedies for the digestive and circulatory organs. During this period, Japanese pharmaceutical companies were also able to launch some of blockbuster drugs. For two decades, the pharmaceutical market grew rapidly. For this reason, it can be called "The Growth Period for Pharmaceutical Products" in Japan. After that period, drug development and sales slowed down due to a lack of expertise in genetic engineering and biotechnologies. This situation caused a large deficit in the trade balance for Japanese pharmaceutical products. However, with regard to the trade balance (including technical royalties) for pharmaceutical product technologies, Japan remains in the black even today.

Racemization, optical resolution and crystallization-induced asymmetric transformation of amino acids and pharmaceutical intermediates.

Tanabe Seiyaku has been investigating an efficient optical resolution method for the productionof optically active amino acids since the 1950s. As one of the practical applications of the resolutionmethods, we focused on crystallization-induced asymmetric transformation, with which it is possibleto obtain more than 50% of one enantiomer of a racemate. In order to achieve the asymmetrictransformation, an elegant method for racemization of optically active amino acids and their saltswas developed. This successful racemization procedure led to efficient and economical preparationpaths for various optically active amino acids by the two crystallization-induced asymmetric transformations,one of which is a combination of enantiomeric resolution and simultaneous racemization and theother is a combination of diastereomeric resolution and simultaneous epimerization. Here, manyexamples of our studies and recent reports of pharmaceutical intermediates are presented.