Research Article InvestigationofCinnamaldehydeDerivativesasPotentialOrganic UV Filters Monica B. Pan, Chloe S. Hughes, Hailey N. Lynch, Marcia M. Schilling, and Anuradha Liyana Pathiranage Austin Peay State University, Clarksville, TN 37044, USA Correspondence should be addressed to Anuradha Liyana Pathiranage; pathiranagea@apsu.edu Received 5 September 2021; Revised 8 February 2022; Accepted 17 February 2022; Published 14 March 2022 Academic Editor: Khaled Mostafa Copyright©2022MonicaB.Panetal.isisanopenaccessarticledistributedundertheCreativeCommonsAttributionLicense, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Long-term exposure to ultraviolet (UV) rays has been attributed to irreversible health defects at the cellular level. Most im- portantly, damage to DNA by UVA and UVB rays can result in uncontrolled cellular growth, leading to skin cancer. As a result, topical treatments have been developed over time to protect the skin from UVA and UVB rays. e active ingredients in sunscreens or sun creams are sometimes unsaturated, aromatic organic compounds capable of absorbing harmful UV photons at a great range of wavelengths. Absorption capabilities of these species depend on their degree of conjugation and their molar absorptivity. With this knowledge, two cinnamaldehyde derivatives were synthesized into five potential organic UV filters by the aldol condensation reaction. e products were identified using nuclear magnetic resonance (NMR) and attenuated total re- flection Fourier-transform infrared (ATR-FTIR) spectroscopies, and ultraviolet-visible (UV-vis) spectroscopy was used to determine the UV absorption range and intensity of absorption for each compound. Since the compounds would hypothetically be utilized in topical ointments to aide in skin protection, these compounds were assessed in the presence of Pseudomonas aeruginosa, a representative bacterium of the skin’s natural flora. A time-course assay was conducted to detect growth effects of P. aeruginosa in the presence of the organic compounds. According to the spectroscopic and bacterial analyses of these UV- blocking compounds, three compounds were determined to be potential UV filters that cover UVA region while demonstrating no apparent harm to the natural skin bacteria P. aeruginosa, while the other two likely diminished bacterial growth by simple niche inhibition. 1. Introduction Sunlight exposure is valued for its benefits to human health, especially its role in the synthesis of vitamin D from cho- lesterol. Unfortunately, prolonged and unprotected exposure to UV rays has been associated with irreversible health defects [1]. e region of UV light emitted by the sun is categorized into three types, which span the following wavelengths: UVA (320–400 nm), UVB (290–320 nm), and UVC (200–290 nm) [2]. Essentially, all UVC rays and a significant portion of UVB rays are absorbed by Earth’s atmosphere and do not penetrate its surface. As a result, UVC ranges of UV light are not typically considered when investigating potential UV filters. Since both UVB and UVA radiation can reach the Earth’s surface and affect the epidermal layer of the skin, broad- spectrum sunscreens are designed to block rays in the UVB and UVA wavelengths [3–5]. UVB rays, while less common on Earth’s surface than UVA rays, have a shorter wavelength and higher energy than UVA rays, and therefore are capable of greater damage to the skin. UVB exposure to the skin can cause mild to severe erythema, typically referred to as sunburn or suntanning, as well as photoaging via collagen degener- ation and abnormal deposition of elastic fibers of the skin [6]. In extreme cases, prolonged and unprotected exposure to UVA and UVB can result in damage to a cell’s DNA which can result in uncontrolled cell growth and skin cancer. While exposure to UVB radiation has been identified as the major contributor to the more harmful effects of solar radiation, studies revealed detrimental effects of long-term exposure to UVA radiation as well. Hindawi Journal of Chemistry Volume 2022, Article ID 7010428, 7 pages https://doi.org/10.1155/2022/7010428