Richard, Thanks for the feedback about the 5th challenge proposal! I take your point that the problem would be more interesting if it incorporated a wide range of test molecules. On the other hand, we've received feedback that the problem is too difficult to do "properly" (i.e. to calculate the saturation composition of the octanol phase which has significant water solubility and related microstructure before you even get to calculating kow for the given molecules). Another practical difficulty is the effort and cost of doing the measurements for a large number of molecules as opposed to a small number. Therefore, my initial thoughts would be that we have to balance scientific interest with practical industrial interest with what is a practical effort for an entrant to devote with what is practical to do in terms of new experimental measurements. Based on that balance, I'm not sure we should expand the list of molecules to a large number. For even a small number of molecules, the problem is at least illustrative of something practical. Jonathan ____________________________ Jonathan Moore, Ph.D. Research and Engineering Sciences - New Products Core R&D The Dow Chemical Company 1702 Building, Office 300E Midland, MI 48674 USA Phone: (989) 636-9765 Fax: (989) 636-4019 E Mail: jmoore2@xxxxxxx ________________________________ From: discuss-ifpsc-bounce@xxxxxxxxxxxxx [mailto:discuss-ifpsc-bounce@xxxxxxxxxxxxx] On Behalf Of IFPSC Sent: Saturday, February 02, 2008 3:46 PM To: discuss-ifpsc@xxxxxxxxxxxxx Subject: [discuss ifpsc] Feedback requested re: 5th IFPSC proposal FYI - some feedback from Richard Elliott ---------- Forwarded message ---------- From: FreeLists Mailing List Manager <ecartis@xxxxxxxxxxxxx> Date: Feb 2, 2008 10:17 AM I think it is a reasonable subject, but I worry about the scope. The molecules should be large enough and new enough that the experimental values are not available in the literature. And there should be 10 of them, covering a range of functionalities that might be interesting as small pharmaceuticals, not just two. JRE