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Marinus Los

  • Born: September 18, 1933, Ridderkerk, The Netherlands

  Interview Details

Interview no.: 0127
Interview Date: January 17, 1995
Location: American Cyanamid Company,
Interviewers: James J. Bohning and Bernadette R. McNulty
No. of pages: 57
Sponsor: Society of Chemical Industry
Society of Chemical Industry

  Abstract of Interview

The interview begins with Dr. Marinus Los' description of his family's origins in The Netherlands. When he was two years old, his family moved to England, where he received his early education during World War II. Encouraged by his older brother, Los studied chemistry at Edinburgh University, where he first became interested in biochemistry. He conducted his Ph.D. research on heterocyclic analogs of azulene under W. H. Stafford. Stafford encouraged Los to study at the National Research Council in Canada. There, he conducted research in the structural chemistry of alkaloids and plants under Leo E. Marion. In 1960, Los became a research chemist at Lederle Laboratories, now a division of the American Cyanamid Company. Under Milon E. Bullock, he conducted early research on insect control via an insect molting hormone discovered by Dr. Peter Karlson. Los also worked on a synthetic steroid project involving anabolic steroids and artificial insemination for cows. He briefly returned to Edinburgh University's Department of Pharmacology to organize a research program in prostaglandins. On returning to American Cyanamid, led at the time by George J. Sella, Jr., Los switched to research on herbicides. In his research on plant growth regulators (PGRs), Los's work on imidazolinones led to the herbicides Assert, Arsenal and Pursuit. This work won him the National Medal of Technology. Los ends the interview by discussing his later career as first Senior Group Leader and then Research Director, focusing on his approach to the encouragement of teamwork at American Cyanamid.


1955 B.Sc., Chemistry, Edinburgh University
1957 Ph.D., Organic Chemistry, Edinburgh University

  Professional Experience

National Research Council of Canada

1958 - 1960 Research Fellow

Edinburgh University

1969 - 1970 Senior Research Fellow, Department of Pharmacology

American Cyanamid Company

1960 - 1971 Senior Research Chemist

American Cyanamid Company

1971 - 1984 Group Leader, Organic Synthesis

American Cyanamid Company

1984 - 1986 Senior Group Leader, Herbicide Discovery

American Cyanamid Company

1986 - 1988 Manager, Crop Protection Chemical Discovery

American Cyanamid Company

1988 - 1992 Associate Director, Crop Sciences

American Cyanamid Company

1992 - 1996 Research Director, Crop Sciences Discovery

American Cyanamid Company

1996 - Present Retired


1954 Boots Drummond Prize in Biochemistry, Edinburgh University
1955 Blandfield Prize in Chemistry, Edinburgh University
1981 Cyanamid Scientific Achievement Award, American Cyanamid Company
1984 Cyanamid President's Award for Excellence in Agriculture, American Cyanamid Company
1990 Distinguished Inventor, Intellectual Property Owners, Inc.
1991 Thomas Alva Edison Patent Award, New Jersey Research & Development Council
1993 National Medal of Technology
1994 Achievement Award, Industrial Research Institute
1994 Perkin Medal, Society of Chemical Industry (American Section)
1995 Award for Creative Invention, American Chemical Society

  Table of Contents

Title and Description Page

Family Background and Early Education 1

Family origins in The Netherlands. Immigration to England. Early education during World War II. Influence of older brother. Introduction to science in high school.

Undergraduate Education 5

Studies in chemistry at Edinburgh University. Burgeoning interest in biochemistry. Projected reunion of graduating class in honors chemistry. First paper with Gerald O. Aspinall on carbohydrate chemistry in plants. Influence of Edmond L. Hirst.

Graduate Education 9

Focus on heterocyclic chemistry. Ph.D. work with W. H. Stafford on heterocyclic analogs of azulene. Research on hydrazine. Award from Industrial Research Institute. Importance of anomalies in research.

National Research Council 12

Research in structural chemistry. Leadership of Leo E. Marion. Papers with Marion and O. E. Edwards on structures derived from alkaloids and plants. Research on the structure of hydroxylycoctonine.

Early Career at Lederle Laboratories 15

Decision to pursue career in industrial science. Interactions with Milon W. Bullock. Early research on insect molting hormone. Development of synthetic anabolic steroids and artificial insemination of cows. Attitude towards publication at Lederle.

Work on Prostaglandins at Edinburgh University 20

Move to Edinburgh University. Start of research program in prostaglandins. Reasons for return to industry.

Herbicide Development at American Cyanamid 22

Research on plant growth regulators (PGRs) and phthalimides. Development of imidazolinones, leading to Avenge. Random screening approach for new herbicides. Discovery of cyclohexyl derivative of phthalimides, leading to Assert, Arsenal, and Pursuit. Joint project with Molecular Genetics. Organizational expansion.

Later Career 38

Promotion to Senior Group Leader. Cyanamid's support of research and development. Influence of George J. Sella, Jr. Views on teamwork and managing creative people. Award of the National Medal of Technology.

Notes 48

Index 50

  About the Interviewer

James J. Bohning

James J. Bohning is professor emeritus of chemistry at Wilkes University, where he was a faculty member from 1959 to 1990. He served there as chemistry department chair from 1970 to 1986 and environmental science department chair from 1987 to 1990. Bohning was chair of the American Chemical Society’s Division of the History of Chemistry in 1986; he received the division’s Outstanding Paper Award in 1989 and has presented more than forty papers at national meetings of the society. Bohning was on the advisory committee of the society’s National Historic Chemical Landmarks Program from its inception in 1992 through 2001 and is currently a consultant to the committee. He developed the oral history program of the Chemical Heritage Foundation, and he was the foundation’s director of oral history from 1990 to 1995. From 1995 to 1998, Bohning was a science writer for the News Service group of the American Chemical Society. He is currently a visiting research scientist and CESAR Fellow at Lehigh University. In May 2005, he received the Joseph Priestley Service Award from the Susquehanna Valley Section of the American Chemical Society.

Bernadette R. McNulty

Bernadette R. McNulty, former oral history project manager for the Chemical Heritage Foundation (CHF), holds a B.A. in communications and social work and an M.A. and Ph.D. in communications. She held several teaching and research-related appointments, including positions at Muhlenberg and Rowan Colleges and Temple University, before joining CHF's oral history program in 1994.

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