Biological activity of 1,3,4-oxadiazole: A bibliometric analysis (2000-2025)

1. INTRODUCTION

The field of medicinal chemistry is continuously in search for new and effective chemical scaffolds to combat various diseases. Among the most privileged structures are heterocyclic compounds, which form the core of a vast number of commercially available drugs [1]. Heterocycles play a significant role in modern drug design [2–6] and have the potential to bind with various active sites or enzyme pockets by Van der Waals hydrophobic and hydrogen bond interactions.

Literature data indicated that the five-membered heterocycles containing nitrogen were studied due to the wide range of biological activities [7–11]. Oxadiazole derivatives, which are a class of five-membered heterocyclic compounds, are of interest to researchers as they are a critical component of pharmacophores and the ligand binding ability [12,13].

According to the position of nitrogen and oxygen atoms, the oxadiazoles are divided into 1,2,3-oxadiazole, 1,2,4-oxadiazole, 1,2,5-oxadiazole, and 1,3,4-oxadiazole (Fig. 1). While 1,2,3-oxadiazole is unstable and rarely used commercially, 1,2,4-oxadiazole, 1,2,5-oxadiazole, and especially 1,3,4-oxadiazole are more stable and widely used in pharmaceuticals, agrochemicals, and materials science. Among these, 1,3,4-oxadiazole is the most prominent in research and commercialization [6,14–19]. Their synthesis has been the focus of attention for a long time [20–22]. Extensive research has demonstrated their potential as anti-diabetic [23], anticancer [24], antimicrobial [25], anti-tuberculosis [26], and anti-inflammatory agents [27–30].

Figure 1. Isomers of oxadiazole. [Click here to view]

The inherent chemical characteristics of 1,3,4-oxadiazole ring’s, such as its polarity, aromaticity, and ability to undergo numerous substitutions, enable its derivatives to interact with a variety of biological targets in an efficient manner. The 1,3,4-oxadiazoles have been investigated in numerous oncology studies to act through a variety of mechanisms, such as the induction of apoptosis and the inhibition of enzymes (such as histone deacetylases and matrix metalloproteinases), making them promising lead compounds for the treatment of a variety of human cell lines. Likewise, their effectiveness against drug-resistant bacterial strains highlights their critical role in combating the antimicrobial resistance. This scaffold acts as a potent bioisostere for functional groups such as esters, amides, and carboxylic acids, offering advantages including improved metabolic stability, enhanced membrane permeability, and favorable pharmacokinetic profiles [6]. They exhibit activity by inhibiting different enzymes and epidermal growth factors such as thymidylate synthase, focal adhesion kinase telomerase, and so on [31]. They have become an essential anchor for drug design [6,32–34] and development due to the existence of this nucleus. Most commercially available antihypertensive agents such as Tiodazosin and Nesapidil and antibiotics such as Furamizole (Fig. 2) contain the oxadiazole nucleus [35,36].

Figure 2. Commercially available drugs containing 1,3,4-oxadiazole nucleus. [Click here to view]

The literature data also showed the applications of substituted 1,3,4-oxadiazoles in liquid crystals, cell imaging agents and as ligands for transition metal ions. The improved electronic and optical properties of 2,5-disubstituted-1,3,4-oxadiazoles emphasized the synthesis of these compounds for use in the Organic Light Emitting Diodes. These molecules have demonstrated significant potential in medicinal chemistry, with numerous studies highlighting their therapeutic promise.

The wide applications of oxadiazole derivatives were an impetus for researchers, leading to vast volumes of articles published over the years. Given the substantial increase in the research on 1,3,4-oxadiazole derivatives, a thorough bibliometric analysis covering the years 2000–2025 is both necessary and timely. Research trends, prominent authors and institutions, regional distributions, and emerging themes in this field are all quantitatively evaluated in such an analysis. This work offers a comprehensive summary of the scaffold’s biological activity and guides future drug development efforts into the most promising directions.

A preliminary scan of bibliometric studies on heterocycles finds only a small number (~seven) of analyses, each with different scopes and methods. To date, no bibliometric analysis has focused specifically on 1,3,4-oxadiazoles, the literature is vast and fragmented, making it difficult to assess research trends, key contributors, and emerging areas. The first archived publication was in the year 1958. Going through the annals of scientific literature on oxadiazole derivatives and their applications can be overwhelming and cumbersome if no proper methodology is used. A bibliometric analysis focusing on the bioactivity of 1,3,4-oxadiazoles, particularly their anticancer and antibacterial properties, is essential due to the growing interest in these heterocyclic compounds in drug discovery.

The main aim of this paper is to organize and report the research on 1,3,4 oxadiazole and its anticancer and antibacterial biological activity in a scientific manner. Among the various biological activities exhibited by 1,3,4-oxadiazoles, anticancer and antibacterial properties are of special importance due to their global health significance, therapeutic urgency, and potential for novel drug discovery. This analysis will offer valuable insights into the evolution and current state of research on 1,3,4-oxadiazoles in the context of anticancer and antibacterial activities. Since studies reviewing research on the anticancer and antibacterial biological activity of 1,3,4 oxadiazole derivative are lacking, the present study will be a foundation for further research. Additionally, it will highlight underexplored areas and potential directions for future. The paper is presented in five sections: Section 1 is the Introduction to the study, Section 2 describes the methodology used, Section 3 presents the results of data analysis, and finally, the last section delivers the conclusion regarding research gaps and helps identify areas for further research.

2. METHODS

Bibliometric analysis offers a systematic, quantitative approach to understanding the structure and evolution of a research field. By examining large volumes of bibliometric data, including authorship, institutional affiliations, countries, and journals, it identifies research clusters, emerging trends, and conceptual relationships [37]. Given the expansive and diverse nature of existing scientific literature, traditional review methods often prove impractical. Bibliometric techniques efficiently summarize vast datasets, providing transparent, objective, and unbiased insights into scholarly output and intellectual development. This rigor and efficiency make bibliometric analysis a valuable tool for mapping scientific progress and guiding future research directions.

The primary goal of this review is to study how research publications related to the 1,3,4-oxadiazole- its biological activity, specifically anticancer and antibacterial activity, evolved over the past 25 years. The study will be structured around five core objectives:

• What is the publication trend for 25 years, from 2000 to 2025?
• Identify the top contributors and research coalition between authors, institutes and countries.
• Conduct science mapping analysis.
• What are the current research trends? Identify emerging research themes related to 1,3,4-oxadiazole and its anticancer and antibacterial bioactivity.
• The study aims to identify the research gaps and provide inputs for further research.

2.2. DATA EXTRACTION

The search equation for the present study aimed to investigate 1,3,4-oxadiazoles’ biological properties, specifically anticancer and antibacterial activity. Thus, the terms “1,3,4-oxadiazole” and “biological activity” were joined by the Boolean operator “AND”; the search terms “anticancer” and “antibacterial” were included and joined by the “OR” operator. The resulting search equation was inquired within the areas of the article title, abstract, and keywords, and the search was limited to document type: articles. The initial extraction of data yielded articles dating back to 1958; it was noticed that there was growth spurt in the late 90s; the study, therefore, was limited to the recent 25 years, starting from 2000 to 2025.

The databases were filtered using the following criteria:

• Keywords: “1,3,4-oxadiazole”, “biological activity”, “bioactivity”, “anticancer”, and antibacterial”
• Document type: Article
• Language: English
• Time: 2000 to 2025

The search criteria used to retrieve data from SCOPUS included the following keywords:

TITLE-ABS-KEY (“1,3,4-oxadiazole” AND (“biological activity” OR “bioactivity” OR “anticancer” OR “antibacterial”)) AND PUBYEAR > 1999 AND PUBYEAR < 2026 AND (LIMIT-TO (DOCTYPE, “ar”)) AND (LIMIT-TO (LANGUAGE, “English”)) AND (LIMIT-TO (PUBSTAGE, “final”)).

Similarly, the search equation used to extract data from the WoS is as follows:

WOS String:

TS=(“1,3,4-oxadiazole”)

AND TS=(“biological activity” OR “bioactivity”)

AND TS=(“anticancer”)

AND TS=(“antibacterial”)

AND PY=(2000-2025)

AND DT=(Article)

AND LA=(English)

TS denotes topic fields (title, abstract, keywords), PY – publications from the last 25 years, LA – Limits to articles written in English language, and DT – Filters only original research articles, not reviews or proceedings. Only peer-reviewed research articles were included, as they represent original findings and comprised about 90% of the dataset. Conference papers (1.1%), book chapters (0.1%), and patents (0%) were negligible, while reviews (8%) were excluded to avoid citation bias, since they typically attract more citations than primary studies.

The information was retrieved on 04th May 2025; the Scopus database yielded 1,215 documents, and the WoS yielded 1,066 documents. From Scopus 1,200 records were retained after deleting the duplicate entries identified. Similarly, from WoS 1,066 records were retrieved in two batches due to download limits (943 + 115); finally, 1,058 records were retained after duplicates were deleted. These two files were merged in R environment and 699 duplicates were identified which were deleted, and a final dataset with 1,559 was used as the input unit for conducting Bibliometric analysis (Fig. 3).

Figure 3. Graphical representation of data collection. [Click here to view]

3. RESULTS

Biblioshiny, a web-based app, was used; Biblioshiny is an open-source visual analysis tool based on the R language Bibliometrix package. VOSviewer 1.6.20 was used to visualize and analyze data. The extracted dataset consisting of 1,559 records was imported into the software for analysis. To gain a comprehensive understanding of the research landscape, various bibliometric visualization and analytical techniques were employed in this study. These methods facilitate the exploration of publication trends, country-wise publication mapping, contributing institutions and leading journals authorship patterns, institutional productivity, and thematic evolution within the selected research domain. The analyses include publication trend analysis, graphical representation of publications by countries, identification of top contributing institutions, co-authorship networks, keyword co-occurrence mapping, thematic mapping, trend and tree mapping, and word cloud generation. These analyses enable a multifaceted understanding of the field—capturing its temporal evolution, geographical and institutional productivity, source distribution, collaborative patterns, and conceptual structure. Each of these approaches provides a distinct yet complementary perspective—together offering an integrated overview of the intellectual structure, collaborative relationships, and emerging research themes in the field. Each analytical method provides unique insights, which, when interpreted together, portray the intellectual organization and emerging trajectories of the research domain.

3.1. Metrics

To show how research output evolves over time publication trend was plotted, depicting the temporal progression of the research topic. Figure 4 reveals the scientific production of articles for the period 2000–2025 highlighting periods of rapid development or stagnation. The annual scientific production graph indicates an upward trend; there were only two articles published in 2000, and the number of publications gradually increased; from the year 2006 onwards, there has been an accelerating growth in the number of articles published. The spatial distribution of productivity, geographic representation of the publications across all countries is depicted in Figure 5.

Figure 4. Publication trend. [Click here to view]

Figure 5. Geographic distribution of publications among countries – Biblioshiny. [Click here to view]

3.1.1. Publication trend (2000–2025)

Table 1 reveals the top 10 leading countries based on the volumes of publications related to 1,3,4-oxadiazoles and their bioactivity. In the period 2000–2024, the country with the highest volume of publications was India, which published 1,752 articles, followed by China, with 644 published. India and China are the leading contributors to research in this field. The observed large numbers (publication units) could be attributed to strong pharmaceutical patent landscapes in these countries, but bibliometric evidence does not confirm causality.

Table 1. Top 10 countries publication and citation metrics.

Country	No: of publications	% (n = 3877)*	No: of citations	Average no. of citations per paper
India	1,752	45.19	11,947	19.8
China	644	16.61	6,308	28.9
Egypt	359	9.26	3,423	44.5
Pakistan	278	7.17	2,522	22.9
Turkey	253	6.53	968	44
Saudi Arabia	200	5.16	883	22.1
Romania	116	2.99	739	9.9
USA	98	2.53	430	17.9
Brazil	93	2.40	418	38
Malaysia	84	2.17	370	13.7

*The total count of n = 3,887 represents the number of country contributions arising from multi-author collaborations. Since a single article may involve authors from multiple countries, this figure exceeds the total article count of 1,559.

3.1.2. Leading journals

To identify the core sources of research and understand the distribution of scholarly output the top contributing leading journals were analyzed along with the article that have received the most citations (Tables 2 and 3). The most significant number of publications appeared in the European Journal of Medicinal Chemistry (72 articles), followed by the Indian Journal of Heterocyclic Chemistry and the Journal of Heterocyclic Chemistry, with 54 articles each.

Table 2. Top cited publications. Data compiled from Scopus and WoS [accessed May 2025].

Title	Year	Journal	Citations	Doc. type
Synthesis, characterization and biological activity of novel 4-thiazolidinones, 1,3,4-oxadiazoles and some related compounds	2002	European Journal of Medicinal Chemistry	440	Article
Synthesis and biological activity of 4-thiazolidinones, thiosemicarbazides derived from diflunisal hydrazide		European Journal of Medicinal Chemistry	338	Article
Synthesis and antimicrobial activity of some new hydrazones of 4-fluorobenzoic acid hydrazide and 3-acetyl-2,5-disubstituted-1,3,4-oxadiazolines	2002	Farmaco	310	Article
Synthesis of some new 1,2,4-triazoles, their Mannich and Schiff bases and evaluation of their antimicrobial activities	2009	European Journal of Medicinal Chemistry	274	Article
Inhibition of tobacco bacterial wilt with sulfone derivatives containing an 1,3,4-oxadiazole moiety	2012	Journal of Agricultural & Food Chemistry	250	Article
Synthesis, physicochemical properties and antimicrobial activity of some new benzimidazole derivatives	2009	European Journal of Medicinal Chemistry	239	Article
Synthesis, antimicrobial and cytotoxic activities of 1,3,4-oxadiazoles, 1,3,4-thiadiazoles and 1,2,4-triazoles	2009	European Journal of Medicinal Chemistry	217	Article
Synthesis and antifungal activities of 5-(3,4,5-trimethoxyphenyl)-2-sulfonyl-1,3,4-thiadiazole and 5-(3,4,5-trimethoxyphenyl)-2-sulfonyl-1,3,4-oxadiazole derivatives	2007	Bioorganic & Medicinal Chemistry	214	Article
Novel 5-(2-hydroxyphenyl)-3-substituted-2,3-dihydro-1,3,4-oxadiazole-2-thione derivatives: Promising anticancer agents	2006	Bioorganic & Medicinal Chemistry	195	Article
Synthesis of novel sulfonamide-1,2,4-triazoles, 1,3,4-thiadiazoles and 1,3,4-oxadiazoles, as potential antibacterial and antifungal agents. Biological evaluation and conformational analysis studies	2012	Bioorganic & Medicinal Chemistry	193	Article

Table 3. Leading journals.

Journals	No: of publications
European Journal of Medicinal Chemistry	72
Indian Journal of Heterocyclic Chemistry	54
Journal of Heterocyclic Chemistry	54
Medicinal Chemistry Research	52
Journal of Molecular Structure	45
Bioorganic Chemistry	35
Molecules	33
Bioorganic and Medicinal Chemistry Letters	31
Asian Journal of Chemistry	30
Bioorganic and Medicinal Chemistry	29

3.1.3. Leading institutions

To identify the major contributors to the advancement of research in this field, an analysis of leading institutions was conducted. Table 4 highlights the universities and research organizations that have produced the highest number of publications and significantly influenced the scholarly output. Figure 6 illustrates the top 10 institutions contributing to publications on 1,3,4-oxadiazole-related research. The major institutional contributor is Guizhou University indicating China’s strong research presence in this domain. Notably, three Indian universities also appear among the top contributors, reflecting India’s growing engagement in this field.

Figure 6. Top 10 institutions contributing to publications on 1,3,4-oxadiazole-related research. [Click here to view]

Table 4. Top 10 institutions publishing studies related to 1,3,4-oxadiazoles.

Institutions	No: of publications
Guizhou University, China	193
Government College University, Pakistan	70
Anadolu University, Turkey	61
National Research Centre, Egypt	59
Karadeniz Technical University, Turkey	47
Cairo University, Egypt	44
Mangalore University, India	44
University of Mysore, India	39
Maharaja Krishnakumarsinhji Bhavnagar University, India	37
Universiti Teknologi Mara, Malaysia	30

3.1.4. Citation analysis

The citation analysis includes both the total number of citations and the average citations per paper. Table 1, which presents country-wise publication information, also provides corresponding citation data. Among the top 10 countries in terms of publication volumes, India is the leading country with the most citations; the figure stands at 11,947, followed by China with 6,308 citations. Egypt has the highest citation average (ratio of citation to publication) of 44.5 citations per paper. Egypt ranks as the third-highest country in article production within this dataset, which could explain the elevated citation impact, as higher output often includes highly cited works.

3.1.5. Author collaboration network

The collaborative relationship between authors is represented by a network diagram, generated using VOSviewer. A fractional counting method was used to focus on substantiative and frequent collaborations; the maximum number of authors per document was limited to 10 documents, the minimum number of documents authored threshold was set at three documents, and 367 met the threshold. The most extensive set of connected items is displayed in Figure 7. The network displays authors as nodes, and the links from each node represent the co-authorship relationship. The size of the node represents the publication count of each author. The network consists of 14 clusters; the major cluster is represented by red and has 16 items, mostly authors from the Indian subcontinent. Research in this cluster focuses on the anticancer bioactivity of 1,3,4-oxadiazoles. The second major cluster, represented by green, has 14 items; most of the research in this cluster is regarding the biological activity of 1,3,4-oxadiazoles.

Figure 7. Co-authorship network. [Click here to view]

3.1.6. Keyword co-occurrence network

A co-occurrence network map of keywords was generated using VOSviewer to explore the thematic structure of the literature on 1,3,4-oxadiazole and its biological activity. The VOSviewer map generated included author keywords with a threshold of 25. Full counting was applied. Normalization method used is the association strength method. Terms that occur together are grouped as a cluster. They were identified via the VOS clustering algorithm with a resolution of 1.0 (default). Minimum cluster size was not specified and it was determined by the algorithm in the software.

The resulting Map, Figure 8, shows three major clusters, each represented by a distinct colour. These clusters reflect major research themes in the field:

Figure 8. Co occurrence map. [Click here to view]

• Cluster 1 (Red): This cluster includes terms such as “Anticancer”, “Apoptosis,” and “Docking Studies”, indicating a focus on the anticancer bioactivity of 1,3,4-oxadiazoles.
• Cluster 2 (Blue): Features terms like “1,3,4-oxadiazole”, “1,2,4-triazole”, “Antibacterial agents”, and “Microbial sensitivity tests’, indicating a focus on heterocyclic chemistry and structure-activity relationships.
• Cluster 3 (Green): Terms such as “Antibacterial activity” and “Antifungal activity” indicate emphasis on the broad-spectrum antimicrobial potential of oxadiazole-based compounds.

The network map shows how oxadiazole-based compounds are being explored multidimensionally across biological, synthetic, and computational domains.

3.1.7. Trend topics

The trend map was analyzed in Biblioshiny based on author keywords; text files containing synonyms were used to filter the database further so terms that mean the same are grouped together and not repeated; also, the following parameters used were: word minimum frequency of 10 which indicates that only those keywords that have 10 or more occurrences are considered for the analysis and number of words per year was limited to 1. The resulting trend graph is Figure 9; the map displays the various trend topics between 2006 and 2025. The vertical line represents the trending keyword, and the length indicates the time the term was trending. The circle size on each line implies the frequency of the term. The larger circles show higher frequency. The topics examined during the time frame (2006–2025) are varied. The frequency of topics antimicrobial activity, anti-tubercular, antifungal, antibacterial, antioxidant activity are of notable interest during 2006–2017. The rise of these bioactivity-related terms shows that 1,3,4-oxadiazole derivatives are being investigated as multi-target therapeutic agents. During the period from 2017 to 2025, the trending topics that have emerged include “density functional theory (DFT)”, “molecular docking”, “Apoptosis”, and “cytotoxicity”; the terms molecular docking and DFT reveal that computational methods are being used to predict, screen, and rationalize bioactivity before experimental testing. DFT is a powerful quantum mechanical modelling method to study the electronic structure of molecules while molecular docking predicts binding interactions with biological targets. The increasing trend of these topics suggests greater dependence on in silico methodology for drug design and understanding molecular interactions. Terms like apoptosis and cytotoxicity suggest studies focused on anticancer or cell-based mechanisms. In the later years, terms like thiadiazoles and 1,2,4-triazoles dominant at the beginning of the period decreased significantly. A range of biological processes like apoptosis and cytotoxicity coupled with disease areas such as anticancer activity, antimicrobial, antifungal and antioxidant, anti-inflammatory, and specific classes of substituted 1,3,4-oxadiazoles compounds indicate the focus on medicinal chemistry research. Importantly, the findings of trend topics suggest computational approaches are increasingly complementing traditional methods such as drug synthesis. These trends reflect an integrated approach in medicinal chemistry, where both experimental and in-silico methodologies are employed to explore the pharmacological potential, molecular mechanisms, and therapeutic applicability of oxadiazole-based compounds.

Figure 9. Trend map based on keywords. [Click here to view]

3.1.8. Thematic map

The thematic map allows for the identification of the most important research topics. Plotting a thematic map aims to identify research gaps, understand if research areas are related, and know where research is presently focused. The thematic map of keywords generated from the studies in the area of 1,3,4-oxadiazoles is illustrated in Figure 10. Thematic maps help show the development and prevalence of keywords with time. The two dimensions of this map’s structure are density (y-axis) and centrality (x-axis). Density shows how developed a topic is, whereas centrality tells about the significance of a theme. The bubbles in the map represent keyword clusters known as a theme; their size depends on the frequency of keywords. The quadrants are labelled motor, basic, emerging or declining and niche themes.

Figure 10. Thematic map based on keywords of research articles on 1,3,4-oxadiazoles and its bioactivity. [Click here to view]

The motor themes quadrant is characterized by high centrality and high density; themes in this quadrant are high-impact research topics. According to Cobo et al. [39], motor themes are organized and well-developed. The keyword terms like “antimicrobial activity,” “3D QSAR,” “insecticidal activity,” “thioether,” and “4-thiazolidinones”, and “thiosemicarbazide” are included in motor themes.

The quadrant below the motor themes to the right is the basic themes quadrant characterized by low density and high centrality; a low density indicates a lack of cohesiveness among the keywords in the theme, and a high centrality indicates a high correlation between other themes in the network; the topics in this quadrant therefore well correlated with other themes are foundational. The basic themes quadrant in the present map has five clusters with topics concentrated around the bioactivity of oxadiazoles. The basic themes topics are underdeveloped, and as research on the above-mentioned topics gains structure, they present significant potential as topics for further research. This category requires further development.

The niche themes represent clusters that reflect high density and low centrality. Though internally cohesive, these research topics also indicate poor relations with the central research field. Studies on MRSA, sulphonamide and piperidine are some of the niche areas of research. This category also includes research on 1,3,4-thiadiazole and 1,2,4-triazole, which—along with 1,3,4-oxadiazole—are five-membered aromatic heterocycles containing two or more heteroatoms (such as nitrogen, oxygen, or sulfur). These keywords highlight a research focus on exploring bioisosteric alternatives to 1,3,4-oxadiazole, which can be interchanged in drug design to optimize biological activity and pharmacological properties.

The last quadrant depicts the declining themes; this quadrant represents clusters with low centrality and density. The topics in this quadrant are not well-researched areas. They also represent clusters that have lost relevance. Anti-inflammatory activity, analgesic and characterization studies are some topics in the declining themes.

3.1.9. Tree map

A tree map helps identify dominant research themes or areas based on their quantitative share in the dataset. In the present study the map was visualized based on the 50 most frequently used author’s keywords. Figure 11 illustrates the tree map; each box nested within the map represents a keyword, and the larger the box, the higher the frequency of the box’s keyword; boxes of the same colour represent clusters. In the present study, the dominant research themes are closely related to the biological activity of 1-3-4-oxadiazoles.

Figure 11. Tree map. [Click here to view]

3.1.10. Word cloud

The word cloud in Figure 12 is a visual representation of the most frequent words, it is preferred over a tree map because it is a better visual aid that helps identify the frequent keywords at a glance. The font size of the keywords is correlated to their frequency. The most frequent keywords are antibacterial activity, followed by 1,3,4-oxadiazole. The frequent keywords are unclassified drug, drug synthesis, structure-activity relationship, oxadiazoles and its derivatives, suggesting a strong focus on developing oxadiazole compounds to be used in medicinal chemistry. Since the unclassified drug is a prominent keyword along with drug synthesis, it can be inferred that 1,3,4-oxadiazole is a compound that is a part of the new investigational drug.

Figure 12. Word cloud. [Click here to view]

Based on the keywords in the word cloud, the research focuses on the design, synthesis and biological evaluation of substituted 1,3,4-oxadiazoles as potential antibacterial and antifungal agents. The terms biological screening, in vitro activity, drug screening and minimum inhibitory concentration suggest that the targets synthesized were assessed for efficiency against different microorganisms. The names of organisms Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus subtilis, and Candida albicans indicate the range of bacteria and fungi studied. The phrase structure-activity relationship reflects the importance of understanding chemical structure relating to biological activity. Most researchers have modified the core structure of 1,3,4-oxadiazoles and attempted to synthesize and characterize the targets by 1 HNMR, 13 CNMR, IR and mass spectrometry. Molecular docking studies were also done to predict the binding interactions. The terms anticancer and antitubercular activity suggest that the substituted 1,3,4-oxadiazoles must be investigated further.

4. LIMITATIONS

• The bibliometric analysis relied exclusively on Scopus and WoS databases. While widely recognized for comprehensive and standardized indexing, this may exclude region-specific or domain-specific research available in databases such as PubMed or local indexing services.
• Bibliometric indicators such as publication volume and citation counts reflect research activity but do not measure the progression of compounds into pre-clinical or clinical trials. Such data are often unpublished and lie outside the scope of bibliometric methods.
• Citation averages for countries with a small number of publications may be skewed by a few highly cited papers, and should therefore be interpreted cautiously.
• Findings are constrained by the methodological scope and the coverage of selected databases, which may not fully represent all relevant literature.

5. CONCLUSION

In conclusion, our study showed that the first reported publication regarding 1,3,4-oxadiazoles was in the year 1958; since then, this research area, which had a production of only five articles in the first decade, has become an area that has drawn considerable interest, with almost 1,200 articles being published in the past 6 years. In terms of volumes of production India and China have been the most significant contributors. The leading journal is the European Journal of Medicinal Chemistry, a reputable journal with a significant impact factor. India has been a country that has produced articles with the highest academic impact in terms of the highest number of citations followed by China, and Egypt has the highest average citation. India China and Egypt are ranked among the top producers of articles and citation impact. A key observation drawn would be that these countries have a strong research ecosystem with well-established institutions, facilities and funding capability. The co-occurrence network map reveals three major clusters of keywords that frequently co-appear in the studies. The trend analysis clearly indicates that much of the topics researched are related to the range of bio-activities. The trend areas also span medicinal chemistry with special thrust on computational methods such as DFT and molecular docking.

The thematic map explains the distribution of topics across strategic zones, in the present study the well developed areas of research are antimicrobial activity and structure-activity relationship. The underdeveloped areas studies related to analgesic and anti-inflammatory studies.

Based on the keywords in the word cloud, the research focuses on the design, synthesis and biological evaluation of substituted 1,3,4-oxadiazoles as potential antibacterial and antifungal agents. The terms biological screening, in vitro activity, drug screening and minimum inhibitory concentration suggest that the targets synthesized were assessed for efficiency against different microorganisms. The names of organisms E. coli, P. aeruginosa, S. aureus, B. subtilis, and C. albicans indicate the range of bacteria and fungi studied. The phrase structure-activity relationship reflects the importance of understanding chemical structure relating to biological activity. Most researchers have modified the core structure of 1,3,4-oxadiazoles and attempted to synthesize and characterize the targets by 1H NMR, 13C NMR, IR and mass spectrometry. Molecular docking studies were also done to predict the binding interactions. The terms anticancer and antitubercular activity suggest that the substituted 1,3,4-oxadiazoles must be investigated further.

Furthermore, it is important to keep investigating the enormous potential of 1,3,4-oxadiazole derivatives in order to discover new therapeutic options. Additionally, computational studies like molecular docking and DFT studies were identified as an emerging area by bibliometric network analysis.

6. ACKNOWLEDGMENTS

The authors acknowledge Mahatma Gandhi University, Nalgonda, Telangana, India and St. John’s PG College, Chengicherla, Medchal-Malkajgiri, Telangana, India.

7. AUTHOR CONTRIBUTIONS

All authors made substantial contributions to conception and design, acquisition of data, or analysis and interpretation of data; took part in drafting the article or revising it critically for important intellectual content; agreed to submit to the current journal; gave final approval of the version to be published; and agree to be accountable for all aspects of the work. All the authors are eligible to be an author as per the International Committee of Medical Journal Editors (ICMJE) requirements/guidelines.

8. FINANCIAL SUPPORT

There is no funding to report.

9. CONFLICTS OF INTEREST

The authors report no financial or any other conflicts of interest in this work.

10. ETHICAL APPROVAL

This study does not involve experiments on animals or human subjects.

11. DATA AVAILABILITY

All claims expressed in this article are solely those of the authors and do not necessarily represent those of the publisher, the editors and the reviewers. This journal remains neutral with regard to jurisdictional claims in published institutional affiliation.

12. PUBLISHER’S NOTE

This journal remains neutral with regard to jurisdictional claims in published institutional affiliation.

13. USE OF ARTIFICIAL INTELLIGENCE (AI)-ASSISTED TECHNOLOGY

The authors used AI-based language assistance tools (such as ChatGPT and Grammarly) solely for improving the clarity and readability of the English text. All scientific content, interpretations, and conclusions were developed by the authors.

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