¶151 CCPA
¶2*1022Byerly, Townsend, Watson & Churchill, New York City (Ralph M. Watson, New York City, and Robert I. Dennison, Washington, D. C., of counsel), for appellant.
¶3Clarence W. Moore, Washington, D. C. (J. E. Armore, Washington, D. C., of counsel), for Comr. of Patents.
¶4Before WORLEY, Chief Judge, and RICH, MARTIN, SMITH and ALMOND, Judges.
¶6Ward appeals from the Board of Appeals’ affirmance of the rejection of his application1 for a patent on a “New Series of Carboxylic Acid Esters of 5-Nitro-2-Furyl Alkylidene Hydroxyalkyl Semicarbazones.”
¶7All of the claims are directed to compounds, useful as chemotherapeuties, which are derived from their corresponding alcohols.
¶8Claim 1 reads:
“1. A carboxylic acid ester of a 5-nitro-2-furyl alkylidene hydroxy-alkyl semicarbazone represented by the formula:
wherein
n represents an integer from 0-1, and R and Ri represent dissimilar groups selected from the class consisting of hydrogen and (lower) al-kanoyloxy (lower) alkyl.”
¶9The references are:
¶10Stillman 2,416,234 February 18, 1949.
¶11Ward 2,656,350 October 20, 1953.
¶12Hayes et al., J. Amer. Chem. Soc., Vol. 77 (1955), page 2282.
¶13Cheronis et al., Semi-micro Qualitative Analysis, Crowell Publishing Company, New York, 1947, pages 179, 180.
¶14Stillman and Ward disclose 5-nitro-2-furaldehyde semicarbazones substituted in the 2 or 4 position by a hydroxyalkyl group. Hayes et al. disclose beta-(5-ni-tro-2-furyl) acrolein 2-(hydroxyalkyl) semicarbazones. Those compounds differ from the compounds being claimed only in one respect, namely, the hydroxy-alkyl substituents of the prior art compounds have been esterified. Thus the claims are drawn to the ester derivatives of prior art alcohols.
¶15Cheronis et al. disclose that it is customary in the identification of alcohols to form simple2 esters thereof. The claimed esters were held to be obvious by the examiner in view of the corre*1023sponding alcohols and the fact that simple esters are customarily formed in the identification of alcohols.
¶16Ward filed two affidavits to show that the claimed esters possess properties which would not be expected from the corresponding alcohols of the prior art. We find it unnecessary to discuss the first affidavit since, the second affidavit, that of O’Connor, establishes that the esters are effective in combatting coc-cidiosis in chickens whereas the corresponding alcohols are devoid of any such activity.
¶17The board agreed with the examiner that since simple esters are customarily prepared to identify the corresponding alcohol, the claimed simple esters were obvious from the prior art alcohols.
¶18As to the affidavits, the board stated:
“ … Appellant also refers to the Hayes and O’Connor affidavits as showing a difference in kind in the esters over the alcohols; however, as to the utility of the affidavits, we agree with the Examiner that they are not convincing that the esters sought to be patented would be unobvious, as the claims are not limited to such utility of the ester compound but are directed to the ester compounds per se. … (Emphasis supplied).
… -K * -»
“ … We, therefore, do not believe that ascertaining that the ester formed is more effective in certain unclaimed uses makes the esters any less obvious. … ”
¶19The examiner, in his Examiner’s Answer before the board, elaborated on that point a bit more:
“ … The rejected claims are not drawn to the contended invention involving the use of the obtained compounds. Insofar as the invention as contended by the applicant does involve the use of the al-kanoic esters now claimed for a certain purpose, the invention if properly claimed would belong to a different statutory class of invention.”
¶20The difficulty with that reasoning is that claims to chemical compounds are drawn to more than structural formulae. They define the compounds themselves and compounds possess properties which must be considered along with the for-mulae.
¶21Here the esters might appear to be obvious in terms of the concept of their structure but that is only half the game. There remains the consideration of the properties of the esters. Ward prepared the claimed esters and, as substantiated by the O’Connor affidavit, discovered that they have the property of being effective in combatting coccidiosis in chickens whereas the corresponding alcohols are totally ineffective. That unexpected property cannot be ignored in the determination of obviousness of the claimed esters as substances and not as structural formulae.3 Indeed, here we find that evidence persuasive of unobviousness and, therefore, are obliged to reverse.
¶22Reversed.