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The selective syntheses of the cyclic monoterpenoids alpha-terpineol or alpha-cyclogeraniol from the acyclic monoterpenoid nerol using p-toluenesulfonic acid or chlorosulfonic acid as cyclizing agents, respectively, are described. The different behavior of nerol under diverse experimental conditions such as nature of the acid agents, solvents, and reaction temperatures is analyzed. The didactic usefulness of these experiments has been rationalized. (Contains 3 schemes.)

Five new bulky moiety-modified analogues of the sandalwood odorant Polysantol® have been synthesized by aldol condensation of appropriate aldehydes with butanone, deconjugative α-methylation of the resulting α,β-unsaturated ketones, and reduction of the corresponding β,γ-unsaturated ketones. The final compounds were evaluated organoleptically and one of them seemed to be of special interest for its natural sandalwood scent. [ABSTRACT FROM AUTHOR]

Triflic acid catalyzed Friedel-Crafts alkylation of aromatics with mono- and bis(trifluoromethyl)oxiranes through ring opening afforded α-(trifluoromethyl) and α,α-bis(trifluoromethyl)-β-phenylethanols in excellent yields. The regioselectivity of the �oxirane ring opening and subsequent Friedel-Crafts alkylation have been found to depend on the electronic and steric effects of the �substituents in the oxirane ring. DFT studies show that C2-O bond is longer than C1-O bond due to high electron-withdrawing effect of CF3 groups effecting C2-O cleavage resulting in a C2 electrophilic center promoting electrophilic substitution with the C2 center on aromatics. [ABSTRACT FROM AUTHOR]

The article describes the reactivity of the monoterpenoid nerol with p-Toluenesulfonic and Chlorosulfonic Acids. The main product when p-toluenesulfonic acid is used as a reagent is α-Terpineol and α-cyclogeranino, 4, is the main product when the superacid chlorosulfonic acid is used as a reagent. The nerol reaction with p-toluenesulfonic acid us conducted at room temperature in a stirred solution of nitromethane or dichloromethane. The reaction of nerol with chlorosulfonic acid is carried out at low temperature in 2-nitropropane.

Cinnamtannin B-1, a natural A-type proanthocyanidin recently identified as a radical scavenger component of Laurus nobilis L., exerts antiaggregant and antiapoptotic effects in human platelets. Here, we have investigated the intracellular mechanisms involved in the antiaggregant effects of cinnamtannin B-1. Cinnamtannin B-1 showed a greater free radical scavenging activity than vitamin C, vitamin E, or Trolox, among other antioxidants and reduced thrombin-evoked tubulin reorganization and platelet aggregation. Thrombin-evoked activation of Btk and pp60(src) was also inhibited by cinnamtannin B-1. In conclusion, we show that cinnamtannin B-1 is a powerful oxygen radical scavenger that reduces thrombin-evoked microtubular remodeling and activation of the tyrosine kinases Btk and pp60(src), which leads to inhibition of platelet aggregation. These observations suggest that cinnamtannin B-1 may prevent thrombotic complications associated to platelet hyperaggregability and hyperactivity, although further studies are necessary to establish appropriate therapeutic strategies.