Appeal No. 95-0334
Application 08/002,513
in yields comparable to prior art methods wherein diacetone-2-
keto-L-gulonic acid (DAGA) is used as the starting material.
Appealed claims 1 and 3-6 stand rejected under 35 U.S.C.
§ 103 as being unpatentable over Fujiwara in view of Bassford
and Japanese '217.
Upon thorough review of the opposing arguments presented
by appellants and the examiner, we concur with appellants that
the examiner has failed to establish a prima facie case of
obviousness for the claimed subject matter. Accordingly, we
will not sustain the examiner's rejection.
The examiner recognizes that Fujiwara discloses making
L-ascorbic acid from either DAGA or GA, but without an
aliphatic ketone being present in the starting reaction
medium. To remedy this deficiency in Fujiwara, the examiner
relies upon the disclosures of Bassford and Japanese '217.
Bassford teaches that when L-ascorbic acid is prepared from
DAGA, a ketone, such as acetone, is liberated and dissolves in
the solvent layer, thereby facilitating its removal from the
reaction medium. Japanese '217 incorporates acetone in a
reaction medium comprising DAGA to dissolve intermediate ester
compounds. Based on the disclosures of Bassford and Japanese
'217, the examiner concludes that it would have been obvious
-3-
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