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2 2017

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D-Rybono-1,4-lakton. Część 2, Wykorzystanie w syntezie organicznej – wybrane reakcje

Madaj J., Samaszko-Fiertek J., Ślusarz R., Dmochowska B.

Wiadomości Chemiczne

2017

[Z] 71, 11-12

861--885

There are many examples of syntheses with d-ribono-1,4-lactone as a substrate. Among all, its biggest advantage is undoubtedly its accessibility. It can be synthesized on a large scale from naturally available raw materials. Its characteristic feature is the stable configuration of individual carbon atoms in multiple reaction conditions. Very important is the presence of a carbonyl moiety, allowing for a variety of additions which is crucial for carbon-carbon bond formation, the most difficult synthesis in organic chemistry. In this article we present selected examples of articles that were published after 1984. In this year, the second article describing the Use of d-Ribonolactone in Organic Synthesis [36] was published. After this time many articles describing the use of the entitled lactone as a substrate in organic synthesis were published. We thought it would be worthwhile to present in Polish a selection of them. C-Glycosides and nucleoside analogs are a particularly important type of synthesized products. Examples of their synthesis are presented in this work, namely, neplanocin A [5], B [31] and F [24], citreovirdin [14], 2-bromopyridin α- and β-d-ribofuranosides [10], 4-deazaformicin A [27] and varitriol [ 33].

D-Rybono-1,4-lakton. Część 1, Otrzymywanie i wybrane pochodne

Madaj J., Samaszko-Fiertek J., Ślusarz R., Dmochowska B.

Wiadomości Chemiczne

2017

[Z] 71, 11-12

844--859

Sugars are extremely important chiral substrates in organic synthesis. Thanks to the possibility of obtaining them from natural sources, their prices are relatively low which increases their attractiveness. d-Ribono-1,4-lactone is included in these compounds. For years it has enjoyed great interest as a substrate. In the early 1980’s two review articles were published in reputable journals [4, 5]. It has been a long time since these articles were published so we have decided to prepare a more up- -to-date review article in Polish. d-Ribono-1,4-lactone can be synthesized in many ways. The most interesting way seems to be the oxidation with KMnO4 [9] or molecular Br2 [10]. The use of bromine may appear to be harmful to the environment. That is why the search for more environmentally friendly methods is ongoing. However, the new methods are not as sufficiently satisfactory and often more expensive than the conventional, previously named methods. Therefore, the most commonly used method is the oxidation of D-ribose with molecular bromine. Very important derivatives of d-ribonolactone are acetal derivatives: 2,3-O-isopropylidene [10, 16] and 3,4-O-benzylidene derivatives [17]. They are often the starting materials for further synthesis. In the case of the latter compound the proper structure was determined by crystallography many years after its synthesis [18]. Very important group of derivatives are derivatives modificated at C-5: sulphonic [21], fluorine [22], chlorine [23], bromine [16, 24], azide [25] and phosphate [27]. Especially important are 5-bromo-5-deoxy derivatives. Examples of their use for the synthesis of thioalditols and thiosugars are described in the literature. It is also worth mentioning the possibility of synthesis of 1,2-unsaturated [28–30] and 2,3-unsaturated [31] derivatives. Presented examples of derivatives prove that using a d-ribono-1,4-lactone a whole range of derivatives extremely useful for further synthesis of more complex compounds can be obtained.