Organic Compounds with Biological Activity

1. Introduction

The Special Issue with the title ‘Organic Compounds with Biological Activity’ [1] was launched at the end 2022. It aimed to collect scientific articles submitted to the journal ‘Compounds’ that either explore the search of organic compounds with biological activity that can have applications in Medicine, Veterinary, Agriculture, and in the disinfection of tools, spaces, and surfaces, or review the biological activities or applications of chemical compounds in these fields.

2. Contributions

Researchers from Europe and from America have published articles in this Special Issue. Together, seven research articles and two reviews have been published, and this editorial is the tenth and last publication in this Special Issue. Of these ten publications, four articles were published by Brazilian researchers, and three by scientists from the United States. Finally, Argentina and Greece are also represented with one publication each (Spain as well if counting this editorial). These publications are summarized and grouped by activities and compound origin in

Table 1. List of the contributions in the Special Issue ‘Organic Compounds with Biological Activity’, grouped by the type of compound or article.

Type of Compound/Article	Title	Activity	Authors	Ref.
Synthetic compounds	Synthesis, Structure, and Anticancer Activity of a Dinuclear Organoplatinum(IV) Complex Stabilized by Adenine	Anticancer	A.M. O’Brien et al.	[2]
	Quinaldehyde o-Nitrobenzoylhydrazone: Structure and Sensitization of HepG2 Cells to Anti-Cancer Drugs	Anticancer	V.V. Mossine et al.	[3]
	Reduction Potential Predictions for Thirty-Seven 1,4-di-N-Oxide Quinoxaline-2-Carboxamide Derivatives with Anti-Tuberculosis Activity	Antibacterial	F. Pooladian et al.	[4]
Natural compounds	Identification of Constituents and Evaluation of Biological Activity of Piptadenia stipulacea (Benth.) Ducke Ethanol Extract	Anticancer and antibacterial	S.A.D.N.M. Silva et al.	[5]
	Protective Effect of Biflavones from Platonia insignis Mart. against Ethidium Bromide-Induced Lethality in Staphylococcus aureus	Cytoprotective	A.S.G. Moura et al.	[6]
	In Vitro Schistosomicidal Activity and Molecular Modeling of Quercitrin and Afzelin Isolated from the Leaves of Copaifera oblongifolia	Antiparasitic	R.C. Ramos et al.	[7]
	Novel Butyrylcholinesterase Inhibitor Alkaloids from Cannabis sativa Roots: Bioguided Isolation and In Silico Study	Anti Alzheimer disease	J.E. Ortiz et al.	[8]
Review articles	Therapeutic Capabilities of Triterpenes and Triterpenoids in Immune and Inflammatory Processes: A Review	Antiinflamatory	M. Mantiniotou et al.	[9]
	Formation and Characterization of Aroma Compounds in Camembert Cheese	Aroma compounds	B.F.D. Ramirez et al.	[10]

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Out of the seven research papers published in this Special Issue, three papers evaluate the biological activity of a series of synthetic compounds [2,3,4], and four works [5,6,7,8] evaluate the biological activity of natural products obtained from different plants. Among the synthetic compounds, two papers focus on the evaluation of specific compounds as anticancer agents, and the third, on the in silico determination of properties of previously reported antibacterial agents.

The first anticancer paper [2], written by O’Brien et al. (from the University of Alaska Fairbanks and Spokane University in USA), reports the synthesis, characterization, structure, and anticancer activity of a platinum organic complex stabilized with the nucleotide adenine, which was evaluated in the panel of 60 human tumor cell lines of the US National Cancer’s Institute Developmental Therapeutics Program.

The second article focuses on anticancer activities and describes the synthesis, characterization, and anticancer activity against the HepG2 cell line exerted by a quinaldehyde o-nitrobenzoyl hydrazone. The paper was prepared by Mossine et al. from the University of Missouri, USA [3].

The last contribution on synthetic compounds was prepared by Pooladian et al. [4] from the Southeast Missouri State University (USA). It reports in silico calculations of the reduction potential of a series of 1,4-di-N-oxide quinoxaline-2-carboxamide derivatives that were reported to have anti-tuberculosis activity in a previous work.

Compounds obtained from plants are the subject of the next four contributions to this Special Issue [5,6,7,8], and interestingly, all of them were developed in South America, in the countries of Brazil [5,6,7] and Argentina [8].

Of these works, the first was written by Silva and coauthors [5] from two Brazilian universities (Universidade Federal do Delta do Parnaíba and Universidade Federal do Piauí). This work intends to determine the flavonoid bioactive compounds extracted with ethanol from Piptadenia stipulacea and reports the anticancer, antioxidant, and antibacterial activity of these compounds.

Compounds from Brazilian flora were also studied in the work of Moura et al. [6] and colleagues from the Federal University of Piauí and Regional University of Cariri. They evaluate the cytoprotective effect exerted by biflavones obtained from Platonia insignis. In particular, these biflavones mitigate the cell damage exerted by ethidium bromide in a Staphylococcus aureus model.

A third study on compounds from Brazilian plants was prepared by Ramos et al. [7] from a team comprising researchers of the Universidade da Franca, Universidade de São Paulo, and the Universidade Federal do Espírito Santo. The authors evaluate the activity in vitro against Schistosoma mansori exerted by quercitrin and afzelin, two compounds obtained from the crude extract of Copaifera oblongifolia.

The last study based on natural compounds was performed by Ortiz et al. [8] and his colleagues from different Argentinian research centers (Universidad Nacional de San Juan, CONICET and Instituto Tecnología de Alimentos, Centro de Investigación de Agroindustria CIA-INTA). This work explores the inhibitory activity of spermidine alkaloids obtained from Cannabis sativa towards enzymes involved in Alzheimer’s disease development, such as the enzymes acetylcholinesterase and butyrylcholinesterase.

Finally, two reviews were published in this Special Issue. The first was written by Mantiniotou et al. [9] from the University of Thessaly in Greece. It revises the potential applications of triterpenes and triterpenoids, found in plant extracts, in the modulation of inflammatory and immune responses. The second review, prepared by Ramirez et al. [10], from the University of Campinas in Brazil, focuses on the characterization of the volatile compounds responsible for the aroma of camembert cheese. It aims to explain how these compounds are formed during cheese production and how this formation can vary depending on certain conditions.

3. Conclusions and Final Remarks

These contributions provide a wide overview of the potential applications of bioactive synthetic compounds and natural compounds. Therefore, we thank all authors who have contributed to this Special Issue ‘Organic Compounds with Biological Activity’, for making this publication in Compounds possible, adding to the rich, interesting, interdisciplinary, and diverse compilation of works at the interface of Chemistry, Physics, Biology, and Pharmacology.

As a final point, we will take this opportunity to invite the entire scientific community to participate in the second edition of this Special Issue, titled ‘Organic Compounds with Biological Activity (2nd Edition)’ [11], through the submission of regular articles, communications, or review articles that fit its scope. We expect this new Special Issue to also be an interesting compilation of valuable and stimulating works that would be of interest for readers of Compounds.