Pizzarello, Sandra

Analysis of carbon compounds—even amino acids—from extraterrestrial sources might provide deeper insights into this mystery. John Cronin and Sandra Pizzarello have examined the enantiomeric distribution of unusual amino acids obtained from the Murchison meteorite, which struck the earth on September 28, 1969, near Murchison, Australia. (By selecting unusual amino... 

Sandra Pizzarello and her team were the first to publish that carbonaceous chon-dritic meteorites contain distinct a-methylated amino acids in low ee (Cronin and Pizzarello 1997 Pizzarello 2006 Pizzarello et al. 2008). As confirmed independently, the Murchison meteorite contained the following nonproteinogenic amino acids in ee 15.2% L-isovaline, 2.8% L-a-methyl-norvaline, 2.8% L-a-methyl-valine, and 9.1% L-a-methyl-isoleucine (Cronin and Pizzarello 1997). As an example, Fig. 3.2 shows the structure of L-a-methyl-norvaline. 

Kenso Soai at the University of Tokyo discovers an auto-catalytic reaction that yields an absolute asymmetric synthesis K. C. Nicolaou, Scripps Research Institute, completes the total synthesis of brevetoxin B John R. Cronin and Sandra Pizzarello, Arizona State University, discover significant excesses of L-enantiomers of uncommon amino acids on the Murchison meteorite... 

Cronin, John R., and Sandra Pizzarello. Enantiomeric Excesses in Meteoric Amino Acids, Science 275 (1997) 951-55. This is the first truly definitive report of an excess of uncommon T.-amino acids on the Murchison meteorite. 

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