Intersting structure???

October 12, 2009 by walkerma

Kim et al. (Bioorg. Med. Chem Lett. ) assign the structure below to a novel neolignan piperkadsin C.  Hmmm??? This can’t be right.

 

piperkadsin C

Name Reactions Misnamed?

September 1, 2009 by walkerma

I am not an  english major, but shouldn’t it be ‘Named Reactions’  (with a ‘d’) instead of  ‘Name Reactions‘.  To me a ‘name reaction’ is what you do in response to hearing a name. Like if someone yelled ‘Hey Shlomo’, Shlomo might turn around to see who called out his name

11-13-2008 A Must Read

November 13, 2008 by walkerma

Chapter 1, Pain induced by blunt force trauma (hammers, anvils, car doors, etc…)

Chapter 2, Oral pain (tooth aches, tongue bites…)

Chapter 3, Pain of the foot (stubbed toes, excessive walking…)

Chapter 4, Miscellaneous (heartache…)

cover-large

September 10, 2008

October 10, 2008 by walkerma

I came across an interesting site that provides useful information for anyone interested in computer aided drug design. BindingMoad.org is a database derived from the PDB, but includes only high resolution protein structures with bound ligands. Other information such as binding data is also included.

long overdue update

October 6, 2008 by walkerma

I was shocked to see how long it has been since I last posted something. It has been much easier to get caught up in other things and let this slip. I am hoping that with this post I can make a new start of it and put up something on a regular basis….at least once a week.

One item for today….Luc Montagnier has won the Nobel prize in medicine for discovering HIV. I imagine this will rankle a few feathers since Robert Gallo, who is also credited the discovery, was not included. For anyone who can remember this is not the first time that there was doubt about Gallo’s role in discovering thie virus. It will be interesting to see how this plays out in the next few weeks.

Personally I am against the idea of assigning credit for any scientific discovery to one or two individuals since it ignores the many other individuals who directly or indirectly contributed.

For Medicinal Purposes…

January 1, 2008 by walkerma

Role of beer as a possible protective factor in preventing Alzheimer’s disease

M.J. González-Muñoz et al. 

Food and Chemical Toxicology, Volume 46, Issue 1, January 2008, Pages 49-56

doi:10.1016/j.fct.2007.06.036  

Useful Site…

December 17, 2007 by walkerma

Separated at birth…

December 16, 2007 by walkerma

Phil Baran (from the pre-prof days) and Scott Baio (‘Chachi’ from ‘Happy Days’). The only way I can tell these two apart is that Phil is pictured with KC.  I bet if Phil were in high school around the same time I was (circa 1978-1982) he would have been tagged with the nickname ‘Chachi’ like my friend Larry who also bore a striking resemblance to this teen TV star.

 small_18029scott_jeanette_2002.jpgbaran2.png

Links

December 13, 2007 by walkerma

Some Interesting Sites:

CrystalEye ”The aim of the CrystalEye project is to aggregate crystallography from web resources, and to provide methods to easily browse, search, and to keep up to date with the latest published information.”

NIH Training Principles of Clinical Pharmacology ”…a series of lectures that cover much of the scientific basis of the bridging discipline of clinical pharmacology.”

UC DAVIS M.I.N.D. Institute Distinguished Lecture Series Webcasts of the distinguished lecture series concerning primarily Autism research.

December 9, 2007 by walkerma

ts2.pngI have carried out simplified analysis of some recent papers on organocatalysis. The first example comes from a paper from the Jacobsen group (Raheem et al. J. Am. Chem. Soc. 2007, 13404, 10.1021/ja076179w) which describes a “H-bond donor” catalyst that effects an enantioselective Pictect-Spengler type reaction. Jacobsen attributes the selectivity to the substrate-halide-catalyst complex shown on the left. However, leaving the halide out of the complex yields an ion pair or perhaps a covalently bound intermediate as shown on the right. This brings the catalyst and substrate into closer contact than the halide-containing complex.

jacobsen.gif

A ground-state model of the des-halide intermediate appears to work in explaining the enantioselectivity of the reaction as shown in the pictures below. In intermediate I, which leads to the minor enantiomer, the indole ring is not able to cyclize onto the acyliminium ion since it is being blocked by an appendage projecting from the catalyst. In contrast when the catalyst is bound to the other face of the acyliminium ion, as in intermediate II, the indole is free to cyclize which leads to the observed dominant enantiomer. Although Jacobsen indicates that some of their experimental work on the mechanism of catalysis makes the direct interaction of the catalyst with the acyliminium less likely, this intermediate is consistent, at least qualitatively, with the stereoselectivity reported for the paper. I am eager to see more details concerning the mechanism to see if this my interpretation holds up.

Intermediate I

intermediatei.png

Intermediate II

intermediateii.png