there are over 30 molecular species of sialics.
Im not sure what the second question is? The masses are as accuarte as
is the purity of the compound.
for general referece see Roland Schauer's book called; Sialic acids,
springer verlag, new york ISBN # 3-211-81707-7. Also a second text,
is Biology of the Sialic acids. ed by Abraham Rosenberg, Plenum
Both are excellent texts. Articles in the latter are particularly well
written. Most of the Chemistry topics are in Schauer's book.
---End of forwarded mail from warner at gene.COM
I hope this helps.
T. Shantha Raju
Analytical Chemistry MS62
460 Point San Bruno Blud.
South San Francisco, CA 94080
email: sraju at gene.com