:Callicarpenal

{{Chembox

| ImageFile = Callicarpenal.svg

| ImageSize = 180px

| IUPACName = 3α-Methyl-14a-homo-12-nor-5β,10α-drim-8-en-14a-al

| SystematicName = [(1S,2R,4aR,8aR)-1,2,4a,5-Tetramethyl-1,2,3,4,4a,7,8,8a-octahydronaphthalen-1-yl]acetaldehyde

| OtherNames = (−)-Callicarpenal; 13,14,15,16-Tetranor-3-cleroden-12-al

|Section1={{Chembox Identifiers

| CASNo = 161105-12-0

| CASNo_Ref = {{cascite|correct|}}

| UNII_Ref = {{fdacite|correct|FDA}}

| UNII = HX4WCL7DPK

| PubChem = 11107286

| ChemSpiderID = 9282422

| SMILES = O=CC[C@@]2([C@@H]1[C@](/C(=C\CC1)C)(CC[C@H]2C)C)C

| InChI = 1/C16H26O/c1-12-6-5-7-14-15(12,3)9-8-13(2)16(14,4)10-11-17/h6,11,13-14H,5,7-10H2,1-4H3/t13-,14+,15+,16+/m1/s1

| InChIKey = MPWIIQYWQOBNKS-UGUYLWEFBV

| StdInChI = 1S/C16H26O/c1-12-6-5-7-14-15(12,3)9-8-13(2)16(14,4)10-11-17/h6,11,13-14H,5,7-10H2,1-4H3/t13-,14+,15+,16+/m1/s1

| StdInChIKey = MPWIIQYWQOBNKS-UGUYLWEFSA-N

}}

|Section2={{Chembox Properties

| C=16 | H=26 | O=1

| Appearance =

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|Section3={{Chembox Hazards

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Callicarpenal is a terpenoid that has been isolated from plants of the genus Callicarpa (beautyberry).{{cite journal | doi = 10.1021/jf0509308 | title = Isolation and Identification of Mosquito Bite Deterrent Terpenoids from Leaves of American (Callicarpa americana) and Japanese (Callicarpa japonica) Beautyberry | year = 2005 | last1 = Cantrell | first1 = C. L. | last2 = Klun | first2 = J. A. | last3 = Bryson | first3 = C. T. | last4 = Kobaisy | first4 = M. | last5 = Duke | first5 = S. O. | journal = Journal of Agricultural and Food Chemistry | volume = 53 | issue = 15 | pages = 5948–53 | pmid = 16028979}} It acts as an insect repellent against mosquitoes (Aedes aegypti and Anopheles stephensi) and fire ants.{{cite journal | pmid = 18459387 | year = 2008 | last1 = Chen | first1 = J | last2 = Cantrell | first2 = CL | last3 = Duke | first3 = SO | last4 = Allen | first4 = ML | title = Repellency of callicarpenal and intermedeol against workers of imported fire ants (Hymenoptera: Formicidae) | volume = 101 | issue = 2 | pages = 265–71 | journal = Journal of Economic Entomology | doi = 10.1603/0022-0493(2008)101[265:ROCAIA]2.0.CO;2| url = https://naldc-legacy.nal.usda.gov/naldc/download.xhtml?id=15346&content=PDF | doi-access = free }} It also has activity against ticks (Ixodes scapularis and Amblyomma americanum).{{Cite journal | pmid = 17380408 | year = 2007 | last1 = Carroll | first1 = JF | last2 = Cantrell | first2 = CL | last3 = Klun | first3 = JA | last4 = Kramer | first4 = M | title = Repellency of two terpenoid compounds isolated from Callicarpa americana (Lamiaceae) against Ixodes scapularis and Amblyomma americanum ticks | volume = 41 | issue = 3 | pages = 215–24 | doi = 10.1007/s10493-007-9057-2 | journal = Experimental & Applied Acarology| s2cid = 13138655 }}

In comparison to the most commonly used insect repellent, DEET, callicarpenal is only about 21% less effective at preventing mosquito bites.{{cite journal | doi = 10.1016/j.tet.2011.02.078 | title = Synthesis of (−)-callicarpenal, a potent arthropod repellent | year = 2011 | last1 = Ling | first1 = Taotao | last2 = Xu | first2 = Jing | last3 = Smith | first3 = Ryan | last4 = Ali | first4 = Abbas | last5 = Cantrell | first5 = Charles L. | last6 = Theodorakis | first6 = Emmanuel A. | journal = Tetrahedron | volume = 67 | issue = 17 | pages = 3023–3029 | pmid = 21643472 | pmc = 3105892}}

Callicarpenal was discovered by scientists at the United States Department of Agriculture's Agricultural Research Service who were inspired by reports that Callicarpa americana (American beautyberry) was used as a folk remedy to prevent mosquito bites.{{Cite journal | url = http://www.ars.usda.gov/is/ar/archive/feb06/mosquito0206.htm | title = Folk Remedy Yields Mosquito-Thwarting Compound | date = February 2006 | journal = Agricultural Research Magazine | volume = 54 | issue = 2 | author = Luis Pons}}