Thyme
Thymus vulgaris (Labiatae) Common thyme
The genus Thymus has about 40 species, but distinguishing between them is difficult.
Common thyme is a native of the Mediterranean countries. Its characteristic flavour is due to the phenols thymol
and carvacrol, adding up to about 70 % of the essential oil [6]. The high content of phenols makes the oil spore-killing and antiseptic. Thymol is also made synthetically. It forms large, colourless, beautifully opalescent crystals (mp. 51. °C).
Thyme oil is sometimes used in masculine perfumes for its spicy, leathery effect.
P.S. Lemon thyme, T. x citriodorus, a crossing between T. vulgaris and T. pulegoides, grows wild in southern France. It contains the terpenic aldehyde citral, and has a fine lemon flavour [103].

phenylacetaldehyde oxime methyl ether

Tobacco
Nicotiana tabacum (Solanaceae) Virginia Tobacco
The tobacco genus, Nicotiana, belongs to the nightshade family and consists of nearly 100 species, mainly
from tropical and subtropical America. The most important species, N. tabacum, or Virginia tobacco, has leaves of 30-50 cm, and large pink flowers. It is not known as a wild plant. Another closely related species, N. rustica, or Rustica tobacco, is also extensively grown. A couple of species are valuable ornamental plants, among them
N. alata and N. x sanderae.
The tobacco plant (N. tabacum) is pictured on a Mexican temple relief from the first century A. D. Tobacco was cultured from Brazil to Mexico long before Columbus, and was brought to Europe by the Spanish explorers in the late 16. century. The knowledge of smoking tobacco was spread with the soldiers during The Thirty Years War.
The flavour of the tobacco leaves has to be developed during a carefully controlled curing process by which a complex mixture of aroma compounds are formed, mainly from oxidative breakdown of carotenoids. A few characteristic compounds are shown above [104]. Variations of this process account for the many types of tobacco. Pipe and cigarette tobaccos are often additionally flavoured, two natural flavouring agents being extracts from sweetclover and tonka beans.
The active principle of tobacco is the alkaloid nicotine, which is produced in the roots, but stored in the leaves. It is a central stimulant in low dose - as in the smoke - but a strong poison in higher concentration. The L.D. 50 of nicotine in mice is 0.3 mg/kg i.v. [70]. The carcinogenic properties of tobacco smoke is mainly due to polycyclic aromatic hydrocarbons (PAHs) - popularly called tar compounds - formed by uncomplete combustion.
Etymology: Nicotiana, in honour of Jean Nicot de Villemain, in 1559-61 the French ambassador in Portugal. He sent a box of pulverized tobacco to Catherine of Medici as a cure against her migraine. Lat. tabacum, from West Indian 'tabaco'.
P.S. Interestingly, Danny Kessler and Ian Baldwin at the Max Planck Institutet for Chemical Ecology in Jena, Germany, have demonstrated that tobacco (Nicotiana attenuata) 'uses' a low level of nicotine in its flower nectar as a 'smart' repellent. The presence of nicotine makes the visits by the pollinators shorter, thereby having more pollinators with the same amount of nectar [168].

Tolu balsam
Myroxylon balsamum (Fabaceae)
Tolu balsam comes from a South American tree, closely related to the tree yielding Peru balsam. 'Tolu balsam resinoid' is obtained by extraction of the raw tolu balsam. It is a brown crystalline mass with a persistent, sweet, balsamic odour, somewhat reminiscent of Hyacint. It is used as a fixative in perfumes.
The main constituents of tolu balsam are the benzyl- and cinnamyl esters of benzoic acid and cinnamic acid. They are solid at room temperature [6].
P.S. The aromatic hydrocarbon toluene (methylbenzene), widely used as a solvent, owes its name to tolu balsam.
In the infancy of organic chemistry, experiments with 'distillation' of tolu balsam yielded 'toluol' by pyrolysis, later to be called toluene (see also benzoe).

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