Archive for the ‘protecting group’ Category

April 14, 2007

April 14, 2007

These are a little overdue… 

Word(s) of the week…Stem cells 

Here in the US Stem Cells have been in the headlines lately. Not the science of stem cells but the politics of stem cells and we in the pharma community have had front row seats on the debate.

On the right, we have politicos such as George Bush and the religious-right who take the position that human embryonic stem cells should be considered “human life” and manipulating these cells for the sake of knowledge violates the “sanctity” of life.  Furthermore, using the ‘slippery slope’ argument the religious groups fear that any use of tissue obtained from abortions would in effect perpetuate the procedure by making it a ‘nessicity’. Therefore, under the current administration the federal government is prohibited from funding stem cell research.

On the other side, we have scientists and patient rights advocates who scoff at the notion that stem cells should be considered “sacred” and view their opponents as being overzealous and major obstacles to the potential treatments of a number of debilitating diseases.

In my opinion, I think both sides are guilty of manipulating the truth to make their point, but being a scientist I am most concerned with the message being put forth by those in favor of stem cell research..I believe we have gone too far in exalting the potential of stems cells to provide cures for such a wide number of diseases in such a short time frame. While I am still young, I have been in the pharma field long enough to know hype when I see it. In my opinion any potential therapy involving stem cells will be decades away if not longer and will likely be successful for only a small set of diseases…Just look how long it took for monoclonal antibodies to make it onto the market…almost 30 years after Kholer and Milstein discovered how to make them. While I am thinking of it…how long have we been working on gene therapy??

Another issue surrounding stem cells that is often not discussed is cost…stem cell therapy will not be cheap by any stretch of the imagination. This is especially relevant considering that most governments have become very cost conscious when it comes to health and the US is on the verge of implementing cost controls on health care…(I won’t talk about the irony of the fact that the politicians who are pushing for stem cell research are the same ones that are behind the cost control legislation)…I expect that the price tag for a typical treatment could be anywhere from $50,000 to $500,000, and with this large price how could we afford to treat conditions such as Parkinsons or Alzheimers which afflict such a large number of people.

Hats off to Paul Knochel

Long before Phil Baran (a brilliant chemist indeed) was promoting protecting-groupless synthesis Paul Knochel and other were challenging people’s assumptions regarding the need for protecting groups in Grignard and Zinc-metallate mediated reactions.  A nice little paper in SynLett shows how to generate Grignard or Zincate of imidazole without the need for protecting groups. The trick here is the use of LiCl which aids the solubility of the reactants and reagents and increases their reactivity. Knochel doesn’t cite it but the current application of LiCl is reminiscent of Seebach’s work use of this salt to increase the solubility of cyclosporin in THF.