Picture of Jonathan Dimmock

Jonathan Dimmock Emeritus Professor

Thorvaldson 211

Dr. Dimmock is a medicinal chemist. He obtained his Ph. D. on the syntheses of candidate narcotic analgesics from the University of London, England and then worked as a research chemist in the industrial sector in the U.K. He joined the faculty of the College of Pharmacy (as it was then) in 1967 and rose to be a full professor in 1976. His teaching was principally devoted to a required course in medicinal chemistry and he initiated an elective on drug design. Much of this latter course was incorporated into a book entitled “An Introduction to Drug Design” which was published in 1997. In 1998 Dr. Dimmock received the University of Saskatchewan Students’ Union Teaching Excellence Award.

In 2002 Dr. Dimmock retired in order to work full time in research principally in conjunction with Dr. Umashankar Das.


The research emphasis of Dr. Dimmock continues to be in the realm of cancer chemotherapy. In practice novel compounds are designed as anticancer drugs which are then synthesised and evaluated for their bioactivity. Specifically the principal group of molecules examined are conjugated unsaturated ketones which have an affinity for thiols and not amino and hydroxyl groups which are found in nucleic acids. An aim is to prepare compounds which demonstrate tumour-selective toxicity which are also effective against multidrug resistant tumours. Use is made of computer software packages which enables the shapes of active and inactive molecules to be compared as well as docking compounds to ascertain the extent of binding of molecules at a binding site of a specific enzyme. The modes of action of bioactive compounds are studied and in particular the effects of the novel compounds on mitochondrial function are noted. X-ray crystallography of representative molecules is undertaken to confirm the proposed structures and to reveal the shapes of molecules.

Other investigations undertaken involved the creation of a number of series of novel anticonvulsants, one of which entered a limited clinical trial. Various antimicrobial and antiparasitical agents have been prepared and a highly effective immunosuppressant was involved in a number of preclinical toxicology experiments.

The supervision or co-supervision of a number of M. Sc. and Ph. D. theses has been accomplished as well as assisting the research of various postdoctoral fellows, Visiting Professors and Visiting Scholars. A number of chapters in books and review articles have also been published. To date these studies have led to approximately 240 refereed articles in a variety of journals along with about 100 Abstracts. In addition Dr. Dimmock has been the external examiner of a number of M. Sc. and Ph. D. theses as well as being a frequent reviewer for manuscripts submitted to various journals.

Recent Publications

A. Chhikara, P.K. Roayapalley, H. Sakagami, S. Amano, K. Satoh, Y. Uesawa, U. Das, S. Das, E.A. Borrego, C.D. Guerena, C.R. Hernandez, R.J. Aguilera, J.R. Dimmock, 2022.  Novel Unsymmetric 3,5-Bis(benzylidene)-4-piperidones That Display Tumor-Selective Toxicity, Molecules, 27, 6718, doi: 10.3390/molecules27196718.

M. Hossain, S. Roth, J.R. Dimmock, U. Das, 2022.  Cytotoxic derivatives of dichloroacetic acid and some metal complexes, Arch Pharm, doi: 10.1002/ardp.202200236.

R.M. Swain, L. Contreras, A. Varela-Ramirez, M. Hossain, U. Das, C.A. Valenzuela, M.L. Penichet, J.R. Dimmock, R.J. Aguilera, 2022.  Two novel piperidones induce apoptosis and antiproliferative effects on human prostate and lymphoma cancer cell lines, Investigational New Drugs, doi: 10.1007/s10637-022-01266-y.

P.K. Roayapalley, J.R. Dimmock, H. Sakagami, N. Okudaira, R.K. Sharma, U.Das, 2022.  1-[4-(2-Dimethylaminoethoxy)phenylcarbonyl]-3,5-Bis(3,4,5-Trimethoxy-benzylidene-4-Piperidone Hydrochloride and Related Compounds: Potent Cytotoxins Demonstrate Greater Toxicity to Neoplasms than Non-Malignant Cells, Medicincal Chemistry, 9, 1001-1012.

M. Hossain, P.K. Roayapalley, H. Sakagami, K. Satoh, K. Bandow, U. Das, J.R. Dimmock, 2022.  Dichloroacetyl Amides of 3,5-Bis(benzylidene)-4-piperidones Displaying Greater Toxicity to Neoplasms than to Non-Malignant Cells, Medicines, 9, 35, doi: 10.3390/medicines9060035.

M. Hossain, S.C. Hall, P.J. Wiggingtom, S.M. Roth, S. Das, U. Das, P.K. Roayapalley, J.R. Dimmock, 2022.  Cytotoxic benzylidene hydrazides of terephthalic acid and related compounds, Pharmazie, 77, 90-94.

P. K. Roayapalley, H. Sakagami, K. Satoh, S. Amano, K. Bandow, R. J. Aguilera, K. G. C. Hernandez, A. Y. S. Bustamante, S. G. Dimmock, R. K. Sharma, U. Das, J. R. Dimmock, 2021. Cytotoxic tumour-selective 1,5-diaryl-3-oxo-1,4-pentadienes mounted on a piperidine ring, Medicines, 8, 78.

P. K. Roayapalley, J. R. Dimmock, L. Contreras, K. S. Balderrama, R. J. Aguilera, H. Sakagami, S. Amano, R. K. Sharma, U. Das, 2021. Design, synthesis and tumour-selective toxicity of novel 1-[3-{3,5-bis(benzylidene)-4-oxo-1-piperidino}-3-oxopropyl]-4-piperidone oximes and related quaternary ammonium salts, Molecules, 26, 7232.

L. Contreras, S. Medina, A.Y. S. Bustamante, E. A. Borrego, C. A. Valenzuela, U. Das, S.S. Karki, J. R. Dimmock, R.J. Aguilera, 2021. Three novel piperidones exhibit tumor-selective cytotoxicity on leukemia cells via protein degradation and stress-mediated mechanisms, Pharmacological Reports, doi.org/10.1007/s43440-021-00322-3.

K. Lakhani, E. A. Borrego, K.G Cano, J. R. Dimmock, R. J. Aguilera, S. Das, P.K. Roayapalley, R. K. Sharma, U. Das, 2021. Design, syntheses and bioevaluations of some novel N2-acryloylbenzohydrazides as chemostimulants and cytotoxic agents, Medicines, 8(27) .doi.org/10.3390.

M. Zandi, A. Farahani, A. Zakeri, S. A. Rezayat, R. Mohammadi, U. Das, J.R. Dimmock, S. Afzali, M. A. Nakhaei, A. Doroudi, Y. Erfani, S.Soltani, 2021. Clinical symptoms and types of samples are critical factors for the molecular diagnosis of symptomatic COVID-19 patients: A systematic literature review.  International Journal of Microbiology, doi.org/10.1155/2021/5528786.

J. R. Nogueira, F.A.Verza, F. Nishimura, U.Das, I.P.Caruso, A.L.Fachin, J.R. Dimmock, M. Marins, 2021.  Molecular docking studies of against SARS-CoV-2 spike protein curcumin analogs, Journal of the Brazilian Chemical Society, doi : org/10.31577/0103-5053.20210085.

A. Doroudi, J. Zhu, J. R. Dimmock, U. Das, 2021. X-ray diffraction study of the crystal structure of 2-[phenyl-(2-hydroxyethylthio)methyl-cyclohexanone, a candidate prodrug of the cytotoxin E-2-benzylidenecyclohexanone, Crystallography Reports, 66(6), 985-990.

F. A. Verza, U. Das, A. L. Fachin, J. R. Dimmock, M. Marins, 2020. Roles of histone deacetylases and inhibitors in anticancer therapy, Cancers, 12, 1664;doi:10:3390.

M. Hossain, C. E. Enci, J. R. Dimmock, U. Das, 2021. Discovery and investigation of 1-[4-(2-aminoethoxy)phenylcarbonl]-3,5-bis(benzylidene)-4-piperidones as candidate antineoplastic agents : Our last 15 years study, Current Medicinal Chemistry, 28(13), 2453-2464.

M. Hossain, S. Das, U. Das, A. Doroudi, J. Zhu, J.R. Dimmock, 2020.  Novel hybrid molecules of 3,5-bis(benzylidene)-4-piperidones and dichloroacetic acid which demonstrate potent tumour-selective cytotoxicity, Bioorganic and Medicinal Chemistry Letters, 30, 126878.

M. Hossain, U. Das, J.R. Dimmock, 2019.  Recent advances in α,β-unsaturated carbonyl compounds as mitochondrial toxins. European Journal of Medicinal Chemistry, 183, 111687.

S. Das, H.I. Gul, U. Das, J. Balzarini, S.G. Dimmock, J.R. Dimmock, 2019.  Novel conjugated unsaturated ketones with submicromolar potencies towards some leukemia and colon cancer cells. Medicinal Chemistry, 15, 430-438.

L. Contreras, R.I. Calderon, A. Varela-Ramirez, H.-Y. Zhang, Y. Quan, U. Das, J.R. Dimmock, R. Skouta, R.J. Aguilera, 2018.  Induction of apoptosis via proteasome inhibition in leukemia/lymphoma cells by two potent piperidones. Cellular Oncology, 41, 623-636.

E. Addala, H. Rafiei, S. Das, B. Bandy, U. Das, S. S. Karki, J. R. Dimmock, 2017. 3,5-Bis(3-dimethylaminomethyl-4-hudroxybenzylidene)-4-piperidone and related compounds induce glutathione oxidation and mitochondria-mediated cell death in HCT-116 colon cancer cells, Bioorganic and Medicinal Chemistry Letters, 27, 3669-3673.