Heather B. Kroona, Ph.D.

Patent Agent
1801 California Street, Suite 3300
Denver, CO 80202
D: 303.357.1186
Contact My Assistant
Amy Doyle
D: 612-371-5310

With a Ph.D. and a post-doctoral fellowship in medicinal chemistry, Heather has a depth and breadth of academic knowledge in both the biological and chemical sciences. She put that knowledge to practical use for over ten years in a variety of hands-on and managerial positions, including five years in pharmaceutical drug research and development as a Chemistry Group Leader and Manager of Process Chemistry at Cortech, Inc., and six years at Heska Corporation directing various groups in process development of recombinant proteins and antibodies for use in various diagnostic platforms.

Now Heather serves clients in the pharmaceutical and biotechnology sciences as a Registered Patent Agent at Merchant & Gould, which she joined in 2008. She spends about half of her time on patent prosecution, preparing and prosecuting patent applications before the U.S. Patent and Trademark Office, responding to office actions, and preparing sequence listings. The remainder of her time is spent on due diligence with patent portfolios and business acquisitions, and on validity analysis for Orange Book-listed patents.

Heather's academic training and years of experience in the lab make her particularly suited to looking at drug design problems for validity analysis. She enjoys working one on one with clients, describing herself as a science geek who likes people.

Heather commutes to work by bicycle, and she enjoys reading, running, yoga, lifting weights, and cooking.


University of Michigan
Postdoctoral Fellow, Medicinal Chemistry, 1992

University of Minnesota
Ph.D. Medicinal Chemistry, 1991

University of Wisconsin, River Falls
B.S. Chemistry, 1985


U.S. Patent and Trademark Office, 2006

Professional Affiliations

American Chemical Society
American Intellectual Property Law Association (affiliate member)

Publications & Speaking


Wieczorek, M.; Gyorkos, A.; Ettinger, A.; Ross, S.E.; Kroona, H.; Burgos-Lepley, C.E.; Bratton, L.D.; Drennan, T.S.; Gernert, D.L.; Von Burg, G.; Pilkington, C.G.; Cheronis, J.C. Biochemical Characterization of alpha-Ketooxadiazole Inhibitors of Elastases, Archives of Biochemistry and Biophysics 1999, 367, 193-201.

Coeschott, C.; Ohnemus, C.; Pilyavskaya, A.; Ross, S.; Wieczorek, M.; Kroona, H.; Leimer, A.H.; Cheronis, J. Converting enzyme-independent release of tumor necrosis factor alpha and IL-1beta from a stimulated human monocytic cell line in the presence of activated neutrophils or purified proteinase 3 Proc. Natl. Acad. Sci. USA 1999, 96, 6261-6266.

Goodfellow, V.S.; Kroona, H.B.; Whalley, E.T.; Wincott, F.E.; Zummach, D.A. Bradykinin Antagonists with Extended Hydrophobic Sidechains, U.S. Patent 5,750,506 May 12, 1998.

Leimer, A.H.; Kroona, H.B.; Blodgett, J.K.; Whalley, E.T.; Ross, S.E.; Burkard, M.R.; Zuzack, J.S.; Gernert, D.L.; Dyckes, D.F. In-vitro Studies of a Bradykinin B1/B2 Antagonist linked to a Human Neutrophil Elastase Inhibitor Can. J. Physiol. Pharmacol. 1997, 75 (6), 633-8.

Mosberg, H.I., Lomize, A.L.; Wang, C., Kroona, H.; Heyl, D.L.; Sobczyk-Kojiro, K.; Ma, W.; Porreca, F. Development of a Model for the delta Opioid Receptor Pharmacophore. 1. Conformationally Restricted Tyr1 Replacements in the Cyclic delta Receptor Selective Tetrapeptide Tyr-c[D-Cys-Phe-D-Pen]-OH (JOM-13). J. Med. Chem. 1994, 37, 4371.

Mosberg, H.I.; Kroona, H.B.; Omnass, J.R.; Sobczyk-Kojiro, K.; Bush, P.; Mousigian, C. Cyclic deltorphin analogs with high delta opioid receptor affinity and selectivity Abstract P412, 13th American Peptide Symposium, June 20-25, 1993.

Mosberg, H.I.; Kroona, H.B. Incorporation of a Novel Restricted Tyrosine Analog into a Cyclic, delta Opioid Receptor Selective Tetrapeptide (JOM-13) Enhances delta Receptor Binding Affinity and Selectivity J. Med. Chem., 1992, 35, 4498.

Peterson, N.L.; Kroona, H.B.; Johnson, R.L.; Koerner, J.F. Activity of the Conformationally Rigid 2-Amino-4-phosphonobutanoic acid (AP4) analog (R,S)-1-amino-3-(phosphonomethylene)cyclobutane-1-carboxylic acid (Cyclobutylene AP-5) on Evoked Responses in the Perforant Path of the Rat Hippocampus, Brain Research 1992, 571, 162.

Kroona, H.B.; Peterson, N.L.; Koerner, J.F.; Johnson, R.L. Synthesis of the 2-amino-4-phosphonobutanoic Acid (AP4) analogues E- and Z- 2-amino-2,3-methano-4-phosphonobutanoic acid and their Evaluation as Inhibitors of Hippocampal Excitatory Neurotransmission, J. Med. Chem. 1991, 34, 1692.

Peterson, N.L.; Kroona, H.B.; Johnson, R.L.; Koerner, J.F. Inhibition of Hippocampal Pathways by Cyclopropyl Analogs of 2-amino-4-phosphonobutanoic Acid (AP4)Abstract, Society for Neuroscience, 1990 Annual Meeting, Oct 28-Nov.2 1990.

Kroona, H.B.; Peterson, N.L.; Koerner, J.F.; Johnson, R.L. Synthesis of Cyclopropyl analogs of 2-amino-4-phosphonobutanoic Acid Abstract 11, Division of Medicinal Chemistry, 198th American Chemical Society (ACS) Meeting, Sept 10-15, 1989.