title: Synthesis and evaluation of novel tetrapropoxycalix[4]arene enones and cinnamates for protection from ultraviolet radiation.
abstract: A series of novel calix[4]arene enones (5-7) and cinnamates (12-14) have been synthesized and evaluated for ensuring protection from ultraviolet radiation (UVR). Spectroscopic analyses has revealed that compound 6 absorbs ultraviolet radiations between 280 and 350 nm with an absorption maximum at 312 nm. Its molar absorption coefficient (ε) (>5 × 10(4)M(-1)cm(-1)) and bandwidth are larger than those for the commercially used sun protectants (oxybenzone (OB), 2-ethylhexyl 4-methoxycinnamate (OMC) and avobenzone). The in vitro Sun Protection Factor (SPF) measurement revealed an SPF of 5.2 at 2% concentration of 6 in home made emulsion formulations while combination of 2% each of 6 and OMC gave an SPF of 8.8. Lower sun protection seems to be compensated by significant protection from more harmful UVA radiations (UVA/UVB absorbance ratio of 0.62).
authors.affiliation: Department of Chemistry, Indian Institute of Technology Delhi, New Delhi 110 016, India. hmchawla@gmail.com
authors.forename: H M
authors.initials: HM
authors.lastname: Chawla
authors.forename: Nalin
authors.initials: N
authors.lastname: Pant
authors.forename: Satish
authors.initials: S
authors.lastname: Kumar
authors.forename: Sarika
authors.initials: S
authors.lastname: Mrig
authors.forename: Bindu
authors.initials: B
authors.lastname: Srivastava
authors.forename: Naresh
authors.initials: N
authors.lastname: Kumar
authors.forename: D Stc
authors.initials: DS
authors.lastname: Black
mesh_terms: D047250:Calixarenes / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D002934:Cinnamates / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology; D006801:Humans; D007536:Isomerism; D010636:Phenols / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D012867:Skin / Q000187:drug effects / Q000528:radiation effects; D013056:Spectrophotometry, Ultraviolet; D013473:Sunscreening Agents / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D014466:Ultraviolet Rays
chemical_list: D002934:Cinnamates; D010636:Phenols; D013473:Sunscreening Agents; C121325:calix(4)arene; D047250:Calixarenes; C063318:4-methoxycinnamic acid