Insect repellent compounds

Abstract

Dihydronepetalactone, a minor natural constituent of the essential oil of catmints ( Nepeta spp.) such as Nepeta cataria , has been identified as an effective insect repellent compound. Synthesis of dihydronepetalactone may be achieved by hydrogenation of nepetalactone, the major constituent of catmint essential oils. This compound, which also has fragrance properties, may be used commercially for its insect repellent properties.

1 . An insect repellent composition comprising 1S,9S,5R,6R-5,9-dimethyl-3-oxabicyclo[4.3.0]nonan-2-one and one or more carriers.  
     
     
         2 . The composition of  claim 1  which comprises 1S,9S,5R,6R-5,9-dimethyl-3-oxabicyclo[4.3.0]nonan-2-one in an amount of from about 0.01% to about 50% by weight of the total weight of the composition.  
     
     
         3 . The composition of  claim 1  further comprising one or more adjuvants.  
     
     
         4 . The composition of  claim 3  wherein the adjuvant is selected from one or more members of the group consisting of thickeners, buffering agents, chelating agents, preservatives, fragrances, antioxidants, gelling agents, stabilizers, surfactants, emollients, coloring agents, aloe vera, waxes, and therapeutically or cosmetically active ingredients.  
     
     
         5 . The composition of  claim 1  wherein the carrier is selected from the group consisting of water, silicone, petrolatum, lanolin, liquid hydrocarbons, agricultural spray oils, paraffin oil, tall oils, liquid terpene hydrocarbons and terpene alcohols, aliphatic and aromatic alcohols, esters, aldehydes, ketones, mineral oil, higher alcohols, finely divided organic and inorganic solid materials and mixtures thereof.  
     
     
         6 . The composition of  claim 1  wherein the carrier comprises an aerosol composition adapted to disperse 1S,9S,5R,6R-5,9-dimethyl-3-oxabicyclo[4.3.0]nonan-2-one into the atmosphere by means of a compressed gas.  
     
     
         7 . The composition of  claim 1  further comprising (9S,5R,1R,6R)-5,9-dimethyl-3-oxabicyclo[4.3.0]nonan-2-one.  
     
     
         8 . The composition of  claim 1  which is in the form of a cologne, a lotion, a spray, a cream, a gel, an ointment, a bath or shower gel, a foam product, makeup, a deodorant, shampoo, a hair lacquer or rinse, a personal soap, an air freshener, a candle, a scented article, a fiber, a sheet, cloth, paper, paint, ink, clay, wood, furniture, carpeting, sanitary goods, a plastic, or a polymer.  
     
     
         9 . An insect repellent composition that consists essentially of 1S,9S,5R,6R-5,9-dimethyl-3-oxabicyclo[4.3.0]nonan-2-one, (9S,5R,1R,6R)-5,9-dimethyl-3-oxabicyclo[4.3.0]nonan-2-one and one or more carriers.  
     
     
         10 . The composition of  claim 9  that further consists essentially of one or more adjuvants.  
     
     
         11 . An insect repellent composition comprising a dihydronepetalactone, or a mixture of dihydronepetalactone stereoisomers, represented by the general formula:  
       
         
           
           
               
               
           
         
       
       and an essential oil selected from one or more members of the group consisting of almond bitter oil, anise oil, basil oil, bay oil, caraway oil, cardamom oil, cedar oil, celery oil, chamomile oil, cinnamon oil, citronella oil, clove oil, coriander oil, cumin oil, dill oil, eucalyptus oil, fennel oil, ginger oil, grapefruit oil, lemon oil, lime oil, mint oil, parsley oil, peppermint oil, pepper oil, rose oil, spearmint oil (menthol), sweet orange oil, thyme oil, turmeric oil, and oil of wintergreen.  
     
     
         12 . The composition of  claim 11  wherein the dihydronepetalactone comprises one or both of 1S,9S,5R,6R-5,9-dimethyl-3-oxabicyclo[4.3.0]nonan-2-one, and (9S,5R,1R,6R)-5,9-dimethyl-3-oxabicyclo[4.3.0]nonan-2-one.  
     
     
         13 . The composition of  claim 11  which comprises dihydronepetalactone in an amount of from about 0.01% to about 50% by weight of the total weight of the composition.  
     
     
         14 . The composition of  claim 11 , which comprises one or more of the members of the group consisting of an adjuvant and a carrier.  
     
     
         15 . The composition of  claim 14 , wherein the adjuvant is selected from one or more members of the group consisting of thickeners, buffering agents, chelating agents, preservatives, fragrances, antioxidants, gelling agents, stabilizers, surfactants, emollients, coloring agents, aloe vera, waxes, and therapeutically or cosmetically active ingredients.  
     
     
         16 . The composition of  claim 14 , wherein the carrier is selected from the group consisting of water, silicone, petrolatum, lanolin, liquid hydrocarbons, agricultural spray oils, paraffin oil, tall oils, liquid terpene hydrocarbons and terpene alcohols, aliphatic and aromatic alcohols, esters, aldehydes, ketones, mineral oil, higher alcohols, finely divided organic and inorganic solid materials and mixtures thereof  
     
     
         17 . The composition of  claim 14 , wherein the carrier comprises an aerosol composition adapted to disperse the dihydronepetalactone into the atmosphere by means of a compressed gas.  
     
     
         18 . The composition of  claim 11 , wherein the essential oil is selected from one or more members of the group consisting of cinnamon oil, citronella oil, eucalyptus oil, ginger oil, grapefruit oil, lemon oil, lime oil, mint oil, peppermint oil, spearmint oil (menthol), sweet orange oil, and oil of wintergreen.  
     
     
         19 . The composition of  claim 11  which is in the form of a cologne, a lotion, a spray, a cream, a gel, an ointment, a bath or shower gel, a foam product, makeup, a deodorant, shampoo, a hair lacquer or rinse, a personal soap, an air freshener, a candle, a scented article, a fiber, a sheet, cloth, paper, paint, ink, clay, wood, furniture, carpeting, sanitary goods, a plastic, or a polymer.  
     
     
         20 . A method of repelling insects comprising exposing the insects to the composition of  claim 1  or the composition of  claim 11 .  
     
     
         21 . The method of  claim 20  wherein the composition is in the form of a gas, liquid or solid.