Darrell E. O'Brien

727 total citations
37 papers, 537 citations indexed

About

Darrell E. O'Brien is a scholar working on Organic Chemistry, Molecular Biology and Nephrology. According to data from OpenAlex, Darrell E. O'Brien has authored 37 papers receiving a total of 537 indexed citations (citations by other indexed papers that have themselves been cited), including 34 papers in Organic Chemistry, 11 papers in Molecular Biology and 2 papers in Nephrology. Recurrent topics in Darrell E. O'Brien's work include Synthesis and Characterization of Heterocyclic Compounds (22 papers), Synthesis and Biological Evaluation (14 papers) and Synthesis and biological activity (13 papers). Darrell E. O'Brien is often cited by papers focused on Synthesis and Characterization of Heterocyclic Compounds (22 papers), Synthesis and Biological Evaluation (14 papers) and Synthesis and biological activity (13 papers). Darrell E. O'Brien collaborates with scholars based in United States. Darrell E. O'Brien's co-authors include Roland K. Robins, Thomas Novinson, K. SENGA, Jon P. Miller, Robert H. Springer, Lionel N. Simon, C. C. Cheng, J. Kobe, Ganapathi R. Revankar and David Streeter and has published in prestigious journals such as Journal of the American Chemical Society, Biochemistry and Journal of Medicinal Chemistry.

In The Last Decade

Darrell E. O'Brien

36 papers receiving 469 citations

Peers — A (Enhanced Table)

Peers by citation overlap · career bar shows stage (early→late) cites · hero ref

Name h Career Trend Papers Cites
Darrell E. O'Brien United States 13 412 148 44 27 20 37 537
Robert H. Springer United States 11 282 0.7× 217 1.5× 35 0.8× 30 1.1× 13 0.7× 29 465
K. SENGA Japan 12 614 1.5× 172 1.2× 37 0.8× 26 1.0× 19 0.9× 103 727
D. J. Brown Australia 11 265 0.6× 148 1.0× 10 0.2× 12 0.4× 30 1.5× 35 378
Louis‐David Cantin Canada 12 190 0.5× 145 1.0× 2 0.0× 77 2.9× 16 0.8× 14 393
David E. Kent Germany 5 349 0.8× 183 1.2× 20 0.7× 30 1.5× 5 494
Arthur A. Santilli United States 11 359 0.9× 140 0.9× 1 0.0× 20 0.7× 4 0.2× 48 440
Herman W. Smith United States 13 172 0.4× 147 1.0× 25 0.9× 17 0.8× 19 431
Marcel Ménard United States 11 218 0.5× 133 0.9× 1 0.0× 22 0.8× 6 0.3× 31 341
W. Werner Zorbach United States 11 300 0.7× 316 2.1× 17 0.6× 13 0.7× 34 465
Kathryn Losee United States 8 376 0.9× 143 1.0× 1 0.0× 68 2.5× 4 0.2× 9 553

Countries citing papers authored by Darrell E. O'Brien

Since Specialization
Citations

This map shows the geographic impact of Darrell E. O'Brien's research. It shows the number of citations coming from papers published by authors working in each country. You can also color the map by specialization and compare the number of citations received by Darrell E. O'Brien with the expected number of citations based on a country's size and research output (numbers larger than one mean the country cites Darrell E. O'Brien more than expected).

Fields of papers citing papers by Darrell E. O'Brien

Since Specialization
Physical SciencesHealth SciencesLife SciencesSocial Sciences

This network shows the impact of papers produced by Darrell E. O'Brien. Nodes represent research fields, and links connect fields that are likely to share authors. Colored nodes show fields that tend to cite the papers produced by Darrell E. O'Brien. The network helps show where Darrell E. O'Brien may publish in the future.

Co-authorship network of co-authors of Darrell E. O'Brien

This figure shows the co-authorship network connecting the top 25 collaborators of Darrell E. O'Brien. A scholar is included among the top collaborators of Darrell E. O'Brien based on the total number of citations received by their joint publications. Widths of edges represent the number of papers authors have co-authored together. Node borders signify the number of papers an author published with Darrell E. O'Brien. Darrell E. O'Brien is excluded from the visualization to improve readability, since they are connected to all nodes in the network.

All Works

20 of 20 papers shown
1.
Robins, Roland K., Ganapathi R. Revankar, Darrell E. O'Brien, et al.. (1985). Purine analog inhibitors of xanthine oxidase ‐ structure activity relationships and proposed binding of the molybdenum cofactor. Journal of Heterocyclic Chemistry. 22(3). 601–634. 91 indexed citations
2.
O'Brien, Darrell E., et al.. (1980). The synthesis of some 4‐nitroisothiazoles as potential antifungal agents. Journal of Heterocyclic Chemistry. 17(2). 385–387. 2 indexed citations
3.
SENGA, K., Roland K. Robins, & Darrell E. O'Brien. (1975). Synthesis of pyrazolo[1′,5′:1,2]‐1,3,5‐triazino[5,6‐a]benzimidazoles. Journal of Heterocyclic Chemistry. 12(5). 899–901. 3 indexed citations
4.
SENGA, K., J. Kobe, Roland K. Robins, & Darrell E. O'Brien. (1975). Synthesis of 1,3‐dialkylpyrazolo [1,5‐a]‐1,3,5‐triazine‐2,4‐diones isomers of 1,3‐dialkylxanthines. Journal of Heterocyclic Chemistry. 12(5). 893–898. 12 indexed citations
5.
Novinson, Thomas, Jon P. Miller, Roland K. Robins, et al.. (1975). Adenosine cyclic 3',5'-monophosphate phosphodiesterase inhibitors. 2. 3-Substituted 5,7-dialkylpyrazolo[1,5-a]pyrimidines. Journal of Medicinal Chemistry. 18(5). 460–464. 28 indexed citations
6.
Novinson, Thomas, Roland K. Robins, & Darrell E. O'Brien. (1973). A novel rearrangement of 3‐cyanopyrazolo[1,5‐a]pyrimidine to a pyrazolo[3,4‐d]pyrimidine. Journal of Heterocyclic Chemistry. 10(5). 887–887. 8 indexed citations
7.
Robins, Roland K., et al.. (1973). Synthesis of 3‐hydroxy‐2,1‐benzisothiazole. Journal of Heterocyclic Chemistry. 10(3). 413–413. 8 indexed citations
8.
Robins, Roland K., et al.. (1973). Synthesis of 2,4‐dimethylpyrazolo[1,5‐a]‐1,3,5‐triazine. Journal of Heterocyclic Chemistry. 10(5). 885–885. 5 indexed citations
9.
Novinson, Thomas, Roland K. Robins, & Darrell E. O'Brien. (1973). A new fluorination procedure. Fluorination of 5,7-dimethylpyrazolo[1,5-a]pyrimidine. Tetrahedron Letters. 14(34). 3149–3150. 2 indexed citations
10.
O'Brien, Darrell E., et al.. (1969). Notes. Synthesis and Antitumor Activity of 9-Substituted Nitrogen Mustard Derivatives of Naturally Occurring Purines. Journal of Medicinal Chemistry. 12(3). 540–542. 1 indexed citations
11.
O'Brien, Darrell E., et al.. (1968). Folic acid analogs. I. p-[[(2,4-Diamino-5-pyrimidinyl)methyl]amino]benzoyl-L-glutamic acid and related compounds. Journal of Medicinal Chemistry. 11(6). 1238–1241. 7 indexed citations
12.
O'Brien, Darrell E., Robert H. Springer, & C. C. Cheng. (1966). A new mannich reaction of pyrimidines. Journal of Heterocyclic Chemistry. 3(1). 115–116. 3 indexed citations
13.
O'Brien, Darrell E., et al.. (1966). Pyrimidines. XVI. 2,4,5-Triaminopyrimidines and Related Compounds1. Journal of Medicinal Chemistry. 9(1). 121–126. 3 indexed citations
14.
O'Brien, Darrell E., et al.. (1965). Synthesis and Antitumor Activity of 9-Substituted Nitrogen Mustard Derivatives of 6-Alkylthiopurines1,2. Journal of Medicinal Chemistry. 8(2). 182–187. 2 indexed citations
15.
O'Brien, Darrell E., et al.. (1963). Pyrimidines. XI. Structural Variations of 2,4-Diamino-6-(halogenoanilino)-5-nitrosopyrimidines1. Journal of Medicinal Chemistry. 6(5). 467–471. 5 indexed citations
16.
Cheng, C. C., et al.. (1963). Studies on Methylglyoxal Bis(guanylhydrazone)1 Analogs. II. Structural Variations on Methylglyoxal Bis(guanylhydrazone)2. Journal of Medicinal Chemistry. 6(4). 431–435. 29 indexed citations
17.
O'Brien, Darrell E., et al.. (1963). Pyrimidines. XII. 1-Substituted 5-Azauracils and Related Compounds*. Biochemistry. 2(6). 1203–1205. 2 indexed citations
18.
O'Brien, Darrell E., et al.. (1962). Pyrimidines. VII. 2-Amino-4-(substituted anilino)pyrimidines1. The Journal of Organic Chemistry. 27(3). 1104–1107. 5 indexed citations
19.
O'Brien, Darrell E., et al.. (1959). Potential Purine Antagonists. XIX. Synthesis of Some 9-Alkyl(aryl)-2-amino-6-substituted Purines and Related V-Triazolo [d]pyrimidines1. Journal of the American Chemical Society. 81(12). 3046–3051. 24 indexed citations
20.
O'Brien, Darrell E., et al.. (1959). Potential Purine Antagonists. XVII. Preparation of Some 6-Alkylthiopurines and 4-Alkylthiopyrazolo[3,4-d]pyrimidines. The Journal of Organic Chemistry. 24(2). 259–261. 8 indexed citations

Rankless uses publication and citation data sourced from OpenAlex, an open and comprehensive bibliographic database. While OpenAlex provides broad and valuable coverage of the global research landscape, it—like all bibliographic datasets—has inherent limitations. These include incomplete records, variations in author disambiguation, differences in journal indexing, and delays in data updates. As a result, some metrics and network relationships displayed in Rankless may not fully capture the entirety of a scholar's output or impact.

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