''Nitzschia Ovalis'' (Bacillariophyceae) Mono Lake strain accumulates 1,4/2,5 cyclohexanetetrol in response to increased salinity



<ref name=post1953a>Th. Posternak and H. Friedli (1953): "Recherches dans la série des cyclitols XVI. Sur quelques cyclohexane‐tétrols‐1,2,3,4". ''Helvetica Chimica Acta'', volume 36, issue 1, pages 251-259. {{doi|10.1002/hlca.19530360131}}</ref>

In 1953, [[Théodore Posternak]] and [[H. Friedli]] obtained the achiral 1,4/2,3 isomer and racemic mixtures of the 1,2/3,4, 1,3/2,4, and 1,2,4/3 isomers.  By biochemical oxydation, they removed the D- enentiomers of the last three, leaving the L- enantiomers.<ref name=post1953a/>

<ref name=post1953b>Théodore Posternak and Dominique Reymond (1953): "Recherches dans la série des cyclitols XVII. Sur l'oxydation de divers cyclitols par Acetobacter suboxydans". ''Helvetica Chimica Acta'', volume 36, issue 1, pages 260-268. {{doi|10.1002/hlca.19530360132}}</ref>

Posternak and Reymond oberved in 1953 that the 1,3/2,4 isomer (D and L forms) is not attacked by a certain strain of ''A. suboxydans'', whereas all the others were metabolized with consumption of 1 atom of oxygen (possibly by formation of a ketone-triol), except the 1,2/3,4 isomer (D and L) that consumed 2 atoms.<ref name=post1953b/>

<ref name=post1955a>Th. Posternak, D. Reymond, W. Haerdi (1955): "Recherches dans la série des cyclitols XX. Chromatographie sur papier de cyclitols et de cycloses". ''Helvetica Chimica Acta'' volume 38, issue 1, pages 191-194  {{doi|10.1002/hlca.19550380122}}</ref>

Posternak, Reymond, and Haerdi described in 1955 separation of cyclitols by paper chromatography in various solvents, and three methods of dvelopment: [[Tollens reagent]]s, the [[Meillère reagent]] (based on the [[Scherer-Gallois reaction]]), and digestion by ''Acetobacter suboxydans'' followed by Tollens reagent.<ref name=post1955a/>

<ref name=post1955b>T. Posternak et al. (1955): ''Helvetica Chimica Acta'', volume 38, pages 208-. </ref>

<ref name=post1955c>T. Posternak and D. Reymond (1955): "Recherches dans la série des cyclitols XXI. Sur la configuration de cyclohexane‐tétrols et ‐triols optiquement actifs. Sur l'oxydation biochimique du cyclohexane‐tétrol‐1,4/2,3 (dihydro‐conduritol)". ''Helvetica Chimica Acta'', volume 38, issue 1, pages 195-205. {{doi|10.1002/hlca.19550380123}}</ref>

In 1955, Posternak and Reymond studied the oxydation of the 1,4/2,3 isomer (dihydro-conduritol) by ''Acetobacter suboxydans'', producing a trihydroxyketone.  They also characterized the chiral isomers 1,3/2,4, 1,2,3/4,and 1,2,4/3.<ref name=post1955c>

<ref name=crie1957>R. Criegee and P. Becher (1957): ''Chemische Berichte'', volume 90, pages 2516-. </ref>

<ref name=bedos1933>Pierre Bedos and Adrien Ruyer (1933): "Sur les oxydes et sur les polyalcools dérivés du cyclohexadiène-1.3.''Comptes rendus hebdomadaires des séances de l'Académie des Sciences'', volume 196, pages 625-627. </ref>

The first 1,2,3,4-cyclohexanetretrols were obtained by [[Pierre Bedos]] and [[Adrien Ruyer]] from hydrolysis of [[1,2;3,4-diepoxy-cyclohexane]].  They separated the reaction products into two isomers, with melting points 210C (tetrabenzoate: 146C) and 187C (tetrabenzoate: 260C), respectively, in 1:2 ratio.<ref name=bedos1933/>

Methods which have been employed for the preparation of 1,2,3,4-cyclohexanetetrols include: reduction or hydrogenation of (1) cyclohexenetetrols, (2) tri-hydroxycyclohexanones, (3) pentahydroxycyclohexanones (inososes), (4) hydroxylated aromatics, or (5) hydroxylated quinones; the (6) hydrogenolysis of dibromocyclohexanetetrols; the (7) hydration of diepoxycyclohexanes; and the hydroxylation of (8) cyclohexadienes or (9) cyclohexenediols. 

<ref name=vale2008>Peter Valente,. Thomas D. Avery, Dennis K. Taylor, and Edward R. T. Tiekink (2008): "Synthesis and Chemistry of 2,3-Dioxabicyclo[2.2.2]octane-5,6-diols". ''Journal of Organic Chemistry'', volume 74, issue 1, pages 274-282. {{doi|10.1021/jo8020506}}</ref>

[[Peter Valente]] and others described the preparation of achiral 1,4/2,3-cyclohexanetetrol ([[toxocarol]]) from  2,3-dioxabicyclo[2.2.2]oct-5-ene, a cyclohexene with a [[peroxyde bridge]] (–O–O–) replacing hydrogens in carbons 3 and 6.  The previous route was reduction of the peroxyde brige to yield 3α,6α-dihydroxy cyclohexene, followed by di-hydoxylation of the double bond; which yielded a mixture of the 1,4/2,3 and 1,2,3,4/0 isomers.   The authors found that, by reversing the order of the two steps, they could obtain 1,4/2,3 in 80% yield.<ref name=vale2008/>