Technological prospection of anti-inflammatory vanilic acid activity, with emphasis on its semisynthetic derivative Isopropyl Vanilate

Inflammation is the body's response to harmful stimuli such as infections, trauma, or injury. The inflammatory cascade can lead to the development of numerous diseases, and the current drug-therapeutic intervention consists of the use of corticosteroids and non-steroidal anti-inflammatory drugs. However, the use of these is associated with several serious side effects, so it is necessary to search for new alternatives that can minimize this effect. In this prospecting, the objective was to conduct a study on biological activities already described for vanillic acid, with special emphasis on its semi-synthetic derivative of isopropyl vanylate as an anti-inflammatory agent. For this, information was obtained on patent documents based on the INPI, USPTO and EPO databases, using the keywords: vanillic acid, anti-inflammatory agents, isopropyl vanylate, always used in the search field related to the summary of works. As results obtained in the present technological prospection study, it was found that in the international patent databases the documents related to the theme were very scarce and some had a higher number of patents, on vanillic acid, few refer to its antiinflammatory, and no documents were found on the use of isopropyl vanillate as an anti-inflammatory agent, reinforcing the innovative character of research involving its use in this technology.


Introduction
Inflammation is the body's response to tissue damage and occurs as a defensive response, which induces profound physiological adaptations triggered in an attempt to limit tissue damage and remove the pathogen. Such mechanisms involve a complex series of events, including the dilation of arterioles, venules and capillaries with increased vascular permeability, fluid exudation, including plasma proteins and leukocyte migration to the inflammatory site. Such an inflammatory response can be triggered by several stimuli, such as: endogenous origin (necrosis tissues, tumor staging), exogenous originating from infections caused by microorganisms, trauma (blunt or penetrating), physical agents (burns or freezing) and chemicals such as radiation and environmental chemicals (Gabay;Kushner, 1999;Lalrinzuali;Vabeiryureilai;Jagetia, 2016;Hu;Shu, 2021).
Although inflammation is a defense mechanism, it is the chronification of this process that leads to deleterious effects on the body, mainly due to the action of mediators involved in this reaction, thus being able to perpetuate and aggravate many diseases (Headland;Norling, 2015;Kumar;Chan;Coussens, 2016;Hou, Michael, Beicheng, 2021). In this context, diseases characterized by the chronicity of the inflammatory process are directly related to the increase in cases of morbidity and mortality, especially in elderly individuals. The inflammatory cascade can lead to the development of diseases such as: rheumatoid arthritis, atherosclerosis, alzheimer, neoplasia, asthma, psoriasis, multiple sclerosis, gastroenteritis, autoimmune diseases and diabetes (Perkins et al., 2015;Who, 2017).
Regardless of the inflammatory process is indispensable for the individual's homeostasis, the deleterious effects caused by this response require, in certain cases, pharmacotherapeutic intervention. The drugs generally prescribed and which are able to interfere in this reaction process of the body are: glucocorticoids or steroidal anti-inflammatory drugs (AIEs) and non-steroidal anti-inflammatory drugs (NSAIDs) ( Figure 5). AINes act by interfering with the synthesis of prostaglandins through unspecific inhibition of the synthesis of COX-1 and / or COX-2. However, the use of these is associated with several serious side effects.
Although effective, the continuous use of NSAIDs is associated with a set of side effects, mainly gastrointestinal toxicity (Horadagoda et al., 1999;Perkins et al, 2015;El-dash et al., 2021).
Gastric injury caused by NSAIDs has generally been associated with non-specific inhibition of cyclooxygenase (COX) isoforms, thereby blocking the production of endogenous substances responsible for gastric reepithelialization, such as the inhibition of prostaglandins (PGs), in particular the PGE2 (Kawahara et al., Gunter, 2017;El-dash et al., 2021). Therefore, the search for therapeutic alternatives that have good anti-inflammatory activity without causing the deleterious effects of current drugs is extremely important. In this sense, natural products are an important source for research aimed at the discovery of new substances with pharmacological activities for the possible development of drugs. In recent years, these natural compounds have guided the development of organic chemistry leading to advances in synthetic methodologies, enabling the synthesis of compounds with chemical structures similar to natural products. At the end of the process, these semisynthetic compounds can be patented, even when their original structure has been previously described (Newman, 2008;Newman 2013;David;Newman et al., 2016;Atanasov et al., 2021).
Gastric injury caused by NSAIDs has generally been associated with non-specific inhibition of cyclooxygenase (COX) isoforms, thereby blocking the production of endogenous substances responsible for gastric reepithelialization, such as the inhibition of prostaglandins (PGs), in particular the PGE2 (Kawahara et al., Gunter, 2017). Therefore, the search for therapeutic alternatives that have good anti-inflammatory activity without causing the deleterious effects of current drugs is extremely important. In this sense, natural products are an important source for research aimed at the discovery of new substances with pharmacological activities for the possible development of drugs. In recent years, these natural compounds have guided the development of organic chemistry leading to advances in synthetic methodologies, enabling the synthesis of compounds with chemical structures similar to natural products. At the end of the process, these semisynthetic compounds can be patented, even when their original structure has been previously described (Newman, 2008;Newman 2013;David;Newman et al., 2016).
In the context of these phenolic compounds, vanillic acid has been highlighted, where experimental studies have provided evidence of its efficacy in cardiovascular, gastrointestinal and liver diseases. In addition, it has anti-inflammatory activity by inhibiting the synthesis of numerous mediators that rise during inflammatory processes in addition to acting directly on lipid peroxidation (Sevgi, Tepe, Sarikurkcu, 2015;Calixto-campos et al., 2015;Dianat et al., 2016;Vinothiya and Ashokkumar, 2017;Nogueira et al., 2019).
In this prospecting, the objective was to conduct a study on biological activities already described for vanillic acid, with special emphasis on its semi-synthetic derivative of isopropyl vanylate as an anti-inflammatory agent. For this, information was obtained on patent documents based on the INPI, USPTO and EPO databases, using the keywords: vanillic acid, antiinflammatory agents, isopropyl vanylate, always used in the search field related to the summary of works. investigating all patent documents available for consultation until the date of the survey (25/02/2021). The searches were carried out using as keywords the terms "vanillic acid", "Anti-inflammatory agents" combined or not and "Isopropyl vanillate", in Portuguese and English together with the Boolean operator "and" in all bases, eventually associating the terms with the use of quotation marks (""). In view of the need to carry out a broader search, such keywords and Boolean operator were always used in the search field related to the summary. The technical procedures applicable to all data collection refer to the search for patent deposits and official collections and databases that provide information on the parameters analyzed in that research were carried out according to the relevant methodology for this type of research (Pereira et al.,2018).

Results and Discussion
The results obtained in the present technological prospecting study refer to all patent deposits made and published on the subject in question recovered through the search used (Figure 1), considering, as regards patent deposits, the country and the year of filing, as well as the International Patent Classification (CIP).
Regarding the international classification, approximately 45.03% of the patents were deposited in the A61 code area of preparation for medical purposes and preparations of compounds with specific activities or medicinal preparations and 54.97% of the patents were deposited in the area of agriculture with codes C7, C8, C12 covering agriculture and specific chemical formulations.
The results of the technological prospecting presented refer, as already mentioned, to the patent documents already filed involving the subject under analysis, in the databases of EPO, INPI, USPTO and WIPO respectively. In the national patent base of the INPI (Figure 1), only 3 patents were found in relation to the keyword vanillic acid involving biocide composition deposited in 2016, the manufacture of an oxidized reaction product deposited in 2015 and the manufacture of a co-crystal and its use to treat thrombotic complications filed in 2012 but no patent related to the biological activity of vanillic acid, on the other hand the search for the term isopropyl vanylate did not return results. It can be observed that when the search for the associated terms was carried out, very poor results were returned showing the potential of the development and the filing of patents related to isopropyl vanylate and its anti-inflammatory activity. The search for a patent at the INPI with the descriptor 'Anti-inflammatory agent' returned 23 results that can be seen in Figure 2, which in summary describe, pharmaceutical compositions of drug combinations and some new anti-inflammatory drugs from natural derivatives such as polysarides, methods alternatives for treating inflammation. On the other hand, the search for the descriptor 'isopropyl vanylate' did not return any results. The American patent base of the USPTO returned 5 results for patents related to the keyword vanillic acid (Figure 3), and are related to the synthesis process, or methods of preparation and production of vanillic acid, only 3 mention the biological activity of the acid vanillic, as a bactericide, antifungal used in the production of co-crystals for platelet inhibition and a patent for combining molecules to treat cancer, but the search for the term isopropyl vanylate did not return results. In the EPO database, 130 patents were found for the keyword vanillic acid as shown in Figure 4, of which only 5 related to its use in inflammation, which describe the use in the treatment of allergic diseases, in the production of capsules to treat urethritis, production of new chemotherapeutic agents for the treatment of cancer, analysis of the analgesic effect of a Chinese plant in which vanillic acid is one of the constituents and production of TNf-α inhibitors. However, for the most part the search corresponds to methods of production, extraction and preparation of extracts containing vanillic acid, as well as in the other database there are some patents for bacterial and antifungal activity. However, when searching for patents using the terms isopropyl vanylate, the search did not return any results. well as new formulations of some that already exist on the market, other patents describe the associated use of anti-inflammatory drugs to treat other diseases, or patents for the production of new drugs, or drugs derived from natural products such as quercetin, which is also a phenolic compound derived as well as vanillic acid. However, no results were returned on this basis after searching for the 'Isopropyl vanillate ad inflammation' association. The search for the keyword 'AntiInflammatory agent' in EPO returned 164 results ( Figure 6). Most of the results are related to the protection of formulations related to the development of non-steroidal anti-inflammatory drugs, as well as new formulations of some that already exist on the market, other patents describe the associated use of anti-inflammatory drugs to treat other diseases, or patents for the production of new drugs, or drugs derived from natural products such as quercetin, which is also a phenolic compound derived as well as vanillic acid. However, no results were returned on this basis after searching for the association 'Isopropyl vanillate and inflammation'.
In Figure 7, it can be seen that companies hold the largest number of patent deposits, with individual inventors in second place and universities in last, showing that this area is quite the target of industries and quite profitable from a commercial point of view. Evidencing the potential of this area for technological development.

Conclusion
Results exposed in this work point out that, although the number of patents filed involving are a relatively small number, with a few hundred deposits, little has been applied in the development of new anti-inflammatory drugs, since the number of patent filing requests involving its association with the treatment of inflammation is scarce, and non-existent in the search for patents involving its semi-synthetic derivative, isopropyl vanylate, which has only one published article demonstrating the Efficacy of a phenol derivative, isopropyl vanillate, as an anti-inflammatory agent: A new small molecule inhibitor of COX and neutrophil migration (Nogueira et al., 2019), thus highlighting the potential of this substance and the importance of its patent.

Individual Inventor
This study may suggest the application and use of Isopropyl Vanylate in several thematic areas, especially in the treatment of inflammation where until now there is only one article proving its effect and effectiveness, such a molecule can represent a good pharmacological target for the treatment of these diseases, since it is a small and easily obtained molecule (apart from vanillic acid).