P- Patchoulene

A biogenetic-like cyclization of a-bulnesol (71) to p-patchoulene (180) occurs to the extent of -- 30% in sulfuric acid-acetic acid, along with simple dehydration and subsequent double bond isomerizations to various bulnesenes and guaienes (263). A more efficient cyclization to (180) (60%) is observed when bulnesol is heated with pyridine and alu-... 

Bang, L., I. G. Guest, et G. Ourisson Transpositions a Etapes Multiples de L Epoxide du p-Patchoulene. Tetrahedron Letters 1972, 2089. 

Closely related to Java patchouli (P. heyneonus) known as false patchouli and sometimes used to produce an essential oil. The true oil is a viscous amber colour with a sweet earthy odour. Its main component is patchouli alcohol (up to 40%) with bulnesene (14-17%), seychellene (8.5-9.5%), caryophyllene (3-4%), 3-patchoulene (2.7-4%). There are a variety of attributed therapeutic properties. For the mind it is said to be a grounding oil helpful for those who feel depressed, detached and exhausted. Applied to the circulation it is considered stimulating, as a diuretic and for skin healing in conditions like acne and eczema. It is often used as a fixative in oriental perfumes, and a deodorizer as it masks unpleasant smells. Due to its very strong odour it is advisable to use in low proportions in a blend. Generally considered to be a safe oil as it is non-irritant and non-sensitizing. 

Oil of Patchouli. Patchouli oil. Essential oil from leaves of several Labiatae species. The commercial oil is obtained from the cultivated species, Pogoslemon cablin (Blanco) Benth. (P. patchouly Pellet, var suavis Hook, f.), Labiatae. Major constituent is patchouli alcohol (cj. i / minor constituents include patchoulene. azulene, eugeno], and several unidentified sesquiterpenes Pfau, Planner, Helv. 

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