Ex parte Markovac et al.

Board of Patent Appeals and Interferences

Feb 17, 1999

08063652 (B.P.A.I. Feb. 17, 1999)

Application for patent filed May 20, 1993. According1
to appellants, this application is a division of Application
No. 07/910,498, filed July 8, 1992, now abandoned.
-1-
THIS OPINION WAS NOT WRITTEN FOR PUBLICATION
The opinion in support of the decision being entered
today (1) was not written for publication in a law
journal and (2) is not binding precedent of the Board.
Paper No. 23
UNITED STATES PATENT AND TRADEMARK OFFICE
________________
BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
________________
Ex parte ANICA MARKOVAC, RICHARD L. KALAMAS
and MAURICE P. LAMONTAGNE
________________
Appeal No. 95-4439
Application No. 08/063,6521
________________
ON BRIEF
________________
Before WINTERS, HANLON and LORIN, Administrative Patent
Judges.
WINTERS, Administrative Patent Judge.
DECISION ON APPEAL
Appeal No. 95-4439
Application No. 08/063,652
-2-
This appeal was taken from the examiner's decision
rejecting claim 18, which is the only claim remaining in the
application.
Appeal No. 95-4439
Application No. 08/063,652
-3-
The appealed claim reads as follows:
-18-
2-Fluoro-9-trimethylsilyladenine.
The references relied on by the examiner are:
Blumbergs et al. (Blumbergs) 5,110,919 May 5, 1992
Kim et al. (Kim) 2-138184 May 28, 1990
(Japanese Kokai patent application)
Calley N. Eaton et al. (Eaton), "Convenient Synthesis of
2-Fluoroadenine," 34 Journal of Organic Chemistry no. 3, 747-
48 (Mar. 1969)
The issue presented for review is whether the examiner
erred in rejecting claim 18 under 35 U.S.C. § 103 as
unpatentable over the combined disclosures of Kim, Eaton and
Blumbergs.
DISCUSSION
On consideration of the record, including the Examiner's
Answer (Paper No. 16) and appellants' "RESPONSE TO NEW GROUND
OF REJECTION UNDER 37 CFR 1.193(b)" (Paper No. 18), we reverse
the rejection under 35 U.S.C. § 103.
Appeal No. 95-4439
Application No. 08/063,652
-4-
In setting forth this rejection, the examiner begins with
purine compounds (II) disclosed by Kim where Y is an amino
group at the 6-position of the ring system and X is hydrogen,
amino, or
Appeal No. 95-4439
Application No. 08/063,652
-5-
mercapto at the 2-position (Kim, English translation, pages 3
and 4).

(II)
The examiner next refers to Kim's trimethylsilylation
reaction, where the above-described purine compounds are
reacted with hexamethyl disilazane (HMDS) to attach a
trimethylsilyl group at the 9-position (Kim, English
translation, page 7). As pointed out by the examiner, Kim's
trimethylsilyl products differ from the compound of claim 18
because the trimethylsilyl products have hydrogen, amino, or
mercapto at the 2-position of the ring system, whereas as the
claimed compound has fluorine at the
2-position. The examiner argues that a person having ordinary
skill in the art, armed with the disclosures of Eaton and
Blumbergs, would have found it obvious to modify the
trimethylsilyl products of Kim by replacing hydrogen, amino,
or mercapto at the 2-position with fluorine. Therefore, the
Appeal No. 95-4439
Application No. 08/063,652
-6-
examiner argues, a person having ordinary skill in the art
would have arrived at the subject matter sought to be patented
in claim 18 in view of the combined disclosures of Kim, Eaton,
and Blumbergs. We disagree.
We have no doubt that the prior art could be modified in
the manner proposed by the examiner. This can be seen from a
review of appellants' specification. The mere fact that the
prior art could be so modified, however, would not have made
the modification obvious unless the prior art suggested the
desirability of the modification. In re Gordon, 733 F.2d 900,
902, 221 USPQ 1125, 1127 (Fed. Cir. 1984). On the facts
presented, we disagree that there is adequate reason,
suggestion, or motivation stemming from the prior art which
would have led a person having ordinary skill from "here to
there," i.e., from the 2-(hydrogen, amino, or mercapto)
products of Kim to the 2-fluoro compound of claim 18.
The Eaton reference, cited in appellants' specification
at page 7, lines 7 and 8, discloses a convenient synthesis of
2-fluoroadenine. Blumbergs discloses an 8-step reaction
sequence for preparing 2-fluoro-ara-AMP (fludarabine
phosphate). See particularly column 2, line 45 through column
Appeal No. 95-4439
Application No. 08/063,652
-7-
4, line 45 of Blumbergs, illustrating the 8-step sequence. In
our judgment, the examiner has impermissibly engaged in a
hindsight reconstruction of the claimed invention, using
appellants' specification as a blueprint or guide and
selecting elements from these disparate references in a
piecemeal manner. This the examiner cannot do. See In re
Gorman, 933 F.2d 982, 986,
18 USPQ2d 1885, 1888 (Fed. Cir. 1991). We believe that the
proposed modification of Kim's trimethylsilyl products, by
replacing 2-(hydrogen, amino, or mercapto) with the 2-fluoro
group taught by Eaton or Blumbergs, constitutes the
impermissible use of hindsight.
The examiner's decision is reversed.
REVERSED
SHERMAN D. WINTERS )
Administrative Patent Judge )
)
)
)
)
ADRIENE LEPIANE HANLON ) BOARD OF PATENT
Administrative Patent Judge ) APPEALS AND
) INTERFERENCES
)
)
Appeal No. 95-4439
Application No. 08/063,652
-8-
)
HUBERT C. LORIN )
Administrative Patent Judge )
clm
Appeal No. 95-4439
Application No. 08/063,652
-9-
Ian C. McLeod
2190 Commons Parkway
Okemos, MI 48864