Furanoic acid

Hydroxymethylfurfural Fructose, glucose 2,5-bis(hydroxymethyl)-furan, 2,5-furandicarboxylic acid, 2,5-furandicarboxaldehyde, 5-fydroxymethyl-furanoic acid, levulinic acid Bicker etaL, 2003 Chheda etal., 2007... 

The phenylosazone from D-xylose 39 can be converted into the pyrazoles 313 [242]. Isoma-Itulose 314 affords the glycosylated aromatic compound 315 [243]. On acidic acetylation the ulosonic acid ester 316 forms concomitantly the glycal derivative 317 and the furanoic acid derivative 318 [244] (O Scheme 63). 

Furancarboxylic acid, Jura n-2-carboxy lie acid, 2-furoic acid, furanoic acid, pyromucic acid, brenzschleimsaiire [88-14-2]... 

Furancarboxylic acid, 5-hydroxymethyl-, 5-hydroxymethyl-2-furoic acid, 5-hydroxymethyl-2-furanoic acid 6338-41-6]... 

Figure 26. Decarboxylation of octyloxy furanoic acid plotted according to the Bawn equation.

The thionation of amides with phosphorus pentasulphide constitutes a traditional synthetic route to thioamides, which have been found to be especially useful for the synthesis of heterocyclic thiones containing the thiolactam grouping.However, thioformylhydroxylamine and some thioamides derived from 2-furanoic acid and anthranilic acid have also been obtained by this reaction. In the latter case, the reaction was performed in pyridine, and the authors were able to isolate the intermediate... 

Like glycolipids, phospholipids are also a elass of polar lipids. Data in Table 3.2 show that phospholipids in natural rubber are normally below 0.6% w/w. A recent study showed that the major components were phosphatidyl choline (PC) and lysophosphatidyl choline (LPC), as shown in Table 3.5. Other minor components were phosphatidyl ethanolamine (PE), phosphatidyl inositol (PI), lysophosphatidyl inositol (LPI), and metal phosphatidates (MP) or phosphatidic acid (PA). Unlike neutral lipids and glycolipids, the acyl components of phospholipids normally contain very low levels of furanoic acid, except for certain rubber clones. The isolated fatty acids are mainly palmitic, stearic, oleic and linoleic acids. ... 

Furano(3,6)pyridazinophane gives with m-chloroperbenzoic acid the corresponding chiral mono-lV-oxide (91) (80JOC4584). 

The oxa-Pictet-Spengler reaction has been used with success to prepare dihydrofurano[2,3-c]pyrans and isochromans from l-(3-furyl)alkan-2-ols and 2-(3 ,4 -dihydroxy)phenylethanol, respectively. Furanyl alcohol 32 reacted with isobutyraldehyde 33 in the presence of p-toluenesulfonic acid to give the corresponding CI5-5,7-diisopropyl 4,5-dihydro-7H-furano[2,3-c]pyran 34 in good yield. ... 

A Friedel-Crafts-type reaction of phenols under basic conditions is also possible. Aqueous alkaline phenol-aldehyde condensation is the reaction for generating phenol-formaldehyde resin.34 The condensation of phenol with glyoxylic acid in alkaline solution by using aqueous glyoxylic acid generates 4-hydroxyphenylacetic acid. The use of tetraalkylammonium hydroxide instead of sodium hydroxide increases the para-selectivity of the condensation.35 Base-catalyzed formation of benzo[b]furano[60]- and -[70]fullerenes occurred via the reaction of C60CI6 with phenol in the presence of aqueous KOH and under nitrogen.36... 

Acid-labile linkages of carbohydrates are commonly those of furano-sidic sugar residues or of deoxy monosaccharides.50,63 Consequently, neuraminic acid and fucose residues, which occur as terminal monosaccharides of protein- and lipid-linked glycans, are removed by hydrolysis with a dilute acid. The linkages formed by these two sugar residues can conveniently be differentiated by subjecting a portion of... 

Treatment of a furan with ortho amino and cyano groups continues to be a viable route to fused pyrimidines. Thus, 2-amino-4,5-di-(2-furanyl)furano-3-carbonitrile produces 5,6-di-(2-furyl)furo[2,3-rf pyrimidin-4(//)-ones in 72% yield upon cyclization in acetic anhydride/formic acid <2006JFIC1129>. 

Dehydration procedures have led to 2//-thiopyrans. Thus unsubstituted parent heterocycle 6 was prepared by the dehydration of hydroxy derivative 287 with potassium hydrogen sulfate.20 The same procedure applied to a mixture of isomeric hydroxy 2-methyl-5,6-dihydro-2//-thiopyrans and 3,5-dihydroxy-2,4,5,6-tetrahydrothiopyran gives all the corresponding thio-pyrans.91 3-Phenylthiopyran dioxide 289 was obtained after the dehydration of hydroxy derivative 288a with phosphoric acid at elevated temperatures.300,301 The same approach was explored for the preparation of furano-2//-thiopyran 14.42... 

Indolines and indoles were prepared by a direct electrochemical reduction of arenediazonium salts. As a result, radical intermediates were generated from which 3,4-disubstituted tetrahydrofuran skeleta were constructed <02OL2735>. A short and stereoselective total synthesis of furano lignans was realized by radical cyclization of epoxides using a transition-metal radical source <02JOC3242>. Other preparations of tetrahydrofurans using radical cyclization include the synthesis of novel amino acids L-bis-... 

Mild thermal rearrangement of the carbonyl azides 408 in 1-methylpyrrole gave l-methyl-A -(2-thiophene)-, l-methyl-iV-(2-selenophene)- and l-methyl-iV-(2-furano)-l//-pyrrole-2-carboxamides 409 in good yields, presumably involving the intermediacy of the corresponding isocyanate (Equation 97) <2000ARK58>. In this case, the successful outcome of such thermal reactions is ascribable to the pronounced acidic property of the pyrrole 2-proton. 

Tanasescu to be anthranil-iV-oxides.201 2Q6,213, 285 Nitrous acid treatment of other 3-arylanthranils (154, X = 0, S) gives, analogously, the furano-130 and thieno-129 quinolones (154, X = 0, S, respectively). 

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