Appeal No. 95-2700
Application 07/956,018
skill in the art because each of Kim and Brown teaches the
formation pyrimidines by reacting "the same-type reactants",
i.e., $-ketoesters with amidines or guanidines (page 3 of
answer). According to the examiner, even though appellants'
reactant is an enol, not a $-keto ester, the enol and keto
ester are tautomers that exist in equilibrium with each other,
such that the claimed reaction with an enol is tantamount to
the prior art reaction with the keto ester. In the words of
the examiner, "the form involved in the reaction, would shift
the equilibrium to producing more of that form until the
entire mixture can be converted to product." (page 6 of
answer).
We cannot subscribe to the examiner's reasoning for
several reasons. First, the examiner has not established on
this record that appellants' reactant (V) exists in tautomeric
equilibrium with the corresponding keto ester, at least to a
sufficiently significant degree that one of ordinary skill in
the art would have been motivated to select the claimed enolic
form as a substitute for the corresponding $-keto ester.
Secondly, even assuming that one of ordinary skill in the art
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