Safety and Efficacy of Sunscreen Formulations Containing Carrier or Non-Carrier-Based UV-Filters
Andreia Ascenso, Sandra Simões, Helena Ribeiro in Carrier-Mediated Dermal Delivery, 2017
Cinnamates are aromatic compounds disubstituted with both an electron-releasing group (OCH3) and an electron-accepting group (ester group further conjugated with a double bond). This allows the extended delocalization of electrons enabling these molecules to absorb at 310 nm [33]. The cinnamates are subject to photo cis-trans isomerization (cis-Z isomer, trans-E isomer). While the E isomer is predominant and has a lmáx = 310 nm, with a molar absorption coefficient (e) of 19,500 dm3mol−1cm−1, the cis isomer, which is formed under sunlight exposure, has a lmáx of 312 nm with a lower e, 10,000 dm3mol−1cm−1. Thus, sunlight exposure results in an equilibrated proportion of E and Z isomers and a consequent decreased absorption of UV light [33].
Novel UV Filtering Agents for Next-Generation Cosmetics: From Phytochemicals to Inorganic Nanomaterials
Madhu Gupta, Durgesh Nandini Chauhan, Vikas Sharma, Nagendra Singh Chauhan in Novel Drug Delivery Systems for Phytoconstituents, 2020
Cinnamates, salicylates octocrylene, and ensulizole are also active organic UV protective agents. Cinnamates are octinoxate (octyl methoxycinnamate [OMC]) and cinoxate (2-ethoxyethyl-methoxycinnamate). OMC is a potent UVB absorber and is the most frequently used sunscreen ingredient. Salicylates are weak UVB absorbers, and they are generally used in combination with other UV filters. Both octisalate and homosalate are water insoluble that leads to their high substantivity, which is the ability to retain its effectiveness after exposure to water and perspiration. Otocrylene has an excellent safety profile with low irritation, phototoxicity, and photoallergic potential and is used in combination with other UV absorbers to achieve higher SPF formulas and to add stability. Ensulizole or phenylbenzimidazole sulfonic acid is water soluble, and it is used in products formulated to feel lighter and less oily, such as daily use cosmetic moisturizers. It is a selective UVB filter, allowing almost all UVA transmission.
Principles of Clinical Diagnosis
Susan Bayliss Mallory, Alanna Bree, Peggy Chern in Illustrated Manual of Pediatric Dermatology, 2005
1. Para-aminobenzoic acid (PABA) and PABA esters – partial UVB and no UVA protection Cinnamates – full UVB protectionBenzophenones – UVB and partial UVA protectionSalicylates – full UVB, and no UVAAvobenzone (Parsol 1789) – UV A, no UVBTitanium dioxide and zinc oxide – physical sunblocks: entire UVB, UVA, visible light protectionTypes of sunscreenPhysical barriers reflect and scatter UVB (e.g. titanium dioxide, zinc oxide; recommended especially for extremely sun-sensitive individualsUVB blockers (e.g. para-aminobenzoic acid (PABA) and its derivatives)UVA blockers (e.g. benzophenone)
Structure–activity relationship investigation of tertiary amine derivatives of cinnamic acid as acetylcholinesterase and butyrylcholinesterase inhibitors: compared with that of phenylpropionic acid, sorbic acid and hexanoic acid
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2018
Xiaohui Gao, Jingjing Tang, Haoran Liu, Linbo Liu, Lu Kang, Wen Chen
In our laboratory, interestingly, several Mannich base derivatives of Flavokawain B with chalcone scaffold were found with AChE inhibitory activity after screening more than one hundred natural products8. Then a series of other chalcone nitrogen-containing derivatives or the analogs were synthesized and also appeared potent AChE inhibitory activity9–12. Based on these investigations, cinnamic acid, a natural compound also containing an α,β-unsaturated carbonyl group, was selected to study in order to develop potential new AChE inhibitors and elucidate the structure–activity relationship. Cinnamic acid and its derivatives are widely used in food13, fragrance material14, cosmetics15 and drugs. It is applied as the scaffold of some drugs in clinic such as Cinepazide16, Tranilast17, Ilepcimide18, etc. It is also employed to be as lead compound or starting material in a few medicinal chemistry investigations.
Serum metabolites reflecting gut microbiome alpha diversity predict type 2 diabetes
Published in Gut Microbes, 2020
Cristina Menni, Jialing Zhu, Caroline I Le Roy, Olatz Mompeo, Kristin Young, Casey M. Rebholz, Elizabeth Selvin, Kari E. North, Robert P Mohney, Jordana T Bell, Eric Boerwinkle, Tim D Spector, Massimo Mangino, Bing Yu, Ana M Valdes
Cinnamic acid is a naturally occurring bioactive compound synthesized in plants by the shikimate pathway, where phenylalanine and tyrosine are two precursor molecules. It is found in plant-based foods such as fruits, vegetables, and whole grains and several potential benefits of cinnamic acid and its derivatives have been demonstrated in in vitro and preclinical studies with regards to T2D, although there is no clinical evidence.35 Cinnamoylglycine is a glycine conjugate of cinnamic acid and it is known to be produced by gut microbes because it is abundant in the serum of conventional mice but present in minimal concentrations in the serum of germfree mice.24 Cinnomoylglycine has substantially greater urinary clearance than creatinine36 and hence accumulates in plasma under conditions of diminished renal function. In our data, we found that the association between cinnomoylglycine, diversity and clinical traits was not affected when adjusting for creatinine. Although its functional effects in humans are unknown, urinary excretion levels of cinnamoylglycine have been proposed as markers of colonization resistance against Clostridium difficile, i.e., as a marker of a healthy gut microbiome that can inhibit the growth of pathogenic microorganisms.37
Synthesis and bioevaluation of new tacrine-cinnamic acid hybrids as cholinesterase inhibitors against Alzheimer’s disease
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2018
Yao Chen, Jie Zhu, Jun Mo, Hongyu Yang, Xueyang Jiang, Hongzhi Lin, Kai Gu, Yuqiong Pei, Liang Wu, Renxiang Tan, Jing Hou, Jingyi Chen, Yang Lv, Yaoyao Bian, Haopeng Sun
The cinnamic acid is a naturally originated compound with diverse biological activity. We notice that several derivatives of cinnamic acid, such as ferulic acid, caffeic acid, are reported to benefit the treatment of AD for many reasons. More importantly, we observe that the cinnamic acid moiety can serve as a good scaffold to insert into the narrow groove of the AChE active site, forming intermolecular interactions with residues in the PAS. Therefore, we consider that cinnamic acid moiety is a good fragment for designing CAS-PAS dual site ChEs inhibitor. However, as a PAS binder, the structural modification of this moiety is not fully analysed previously. Herein, we designed a series of tacrine-cinnamic acid hybrids, and discussed the SAR for these compounds as dual site ChEs inhibitors.
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