Biosynthesis of rare hexoses using microorganisms and related enzymes

• Zijie Li,
• Yahui Gao,
• Hideki Nakanishi,
• Xiaodong Gao and
• Li Cai

Beilstein J. Org. Chem. 2013, 9, 2434–2445, doi:10.3762/bjoc.9.281

• transformations have become a very powerful tool in this field. This article reviews the biosynthesis and enzymatic production of rare ketohexoses, aldohexoses and sugar alcohols (hexitols), including D-tagatose, D-psicose, D-sorbose, L-tagatose, L-fructose, 1-deoxy-L-fructose, D-allose, L-glucose, L-talose, D

• of rare ketohexoses The most common ketohexoses (ketone-containing hexoses), each of which represents a pair of enantiomers (D- and L-isomers), include tagatose, psicose, sorbose, and fructose. Among the eight sugars, D-tagatose, D-psicose, D-sorbose, L-tagatose and L-fructose are generally regarded

• as rare sugars due to their low abundance in nature. In addition, 1-deoxy-L-fructose is also a very rare but important monosaccharide [8]. The biosynthesis of these rare ketohexoses using microorganisms and related enzymes is summarized below. D-Tagatose D-Tagatose is a keto-/aldo-isomer of D

Flow synthesis of a versatile fructosamine mimic and quenching studies of a fructose transport probe

• Matthew B. Plutschack,
• D. Tyler McQuade,
• Giulio Valenti and
• Peter H. Seeberger

Beilstein J. Org. Chem. 2013, 9, 2022–2027, doi:10.3762/bjoc.9.238

• . Performing this step in flow enables a ~64-fold throughput enhancement relative to batch. The flow process enables the synthesis to be accomplished three times faster than the comparable batch route. The high throughput enabled the production of larger quantities of the fluorescent fructose transport probe

• NBDM, enabling us to measure key photophysical properties that will facilitate future uptake studies. Keywords: flow chemistry; fructose mimic; gluts; NBDM; Introduction The impact of dietary fructose on human health is not well-understood. A growing body of work suggests that those eating diets high

• in fructose exhibit increased rates of metabolic disorders and aggressive cancers [1][2]. Since the landmark reports from Warburg [3], researchers have recognized that cancer cells/tissues consume more carbohydrates than normal tissues, fueling rapid growth and proliferation [4]. While cancer cells

Exploration of an epoxidation–ring-opening strategy for the synthesis of lyconadin A and discovery of an unexpected Payne rearrangement

• Brad M. Loertscher,
• Yu Zhang and
• Steven L. Castle

Beilstein J. Org. Chem. 2013, 9, 1179–1184, doi:10.3762/bjoc.9.132

• sluggish and required superstoichiometric amounts of Shi’s fructose-derived ketone 16 [27]. The resulting epoxide 17 was produced in moderate yield but excellent (<95:5) diastereomeric ratio (Scheme 3). The epoxide stereochemistry was assigned based on the reported outcomes of epoxidations mediated by 16

Quantification of N-acetylcysteamine activated methylmalonate incorporation into polyketide biosynthesis

• Stephan Klopries,
• Uschi Sundermann and
• Frank Schulz

Beilstein J. Org. Chem. 2013, 9, 664–674, doi:10.3762/bjoc.9.75

• agar piece was used to inoculate the preculture, 7 mL RapV7 Seed Medium [47] supplemented with 0.16 mL 20% glucose, and cultivated for 48 h at 180 rpm and 28 °C. The main culture in 7 mL MD6 medium [47] (supplemented with 0.35 mL 40% fructose and 0.1 mL L-lysine (140 mg/mL)) was mixed with feeding

New modification of the Perkow reaction: halocarboxylate anions as leaving groups in 3-acyloxyquinoline- 2,4(1H,3H)-dione compounds

• Oldřich Paleta,
• Karel Pomeisl,
• Stanislav Kafka,
• Antonín Klásek and
• Vladislav Kubelka

Beilstein J. Org. Chem. 2005, 1, No. 17, doi:10.1186/1860-5397-1-17

• reaction of halocompounds, the observed leaving groups were the halogen anions. However, in the reaction of pentaacetylated D-fructose with trimethyl phosphite the acetyloxy anion as the leaving group was also observed. [10] This rather unusual transformation may be attributed to the structural nature of

• utilizing fructose pentaacetate,[10] the 3-acetoxyquinoline-2,4(1H,3H)-diones 7a and 7b did not react (Table 1, entries 6 and 7). In both of the reactions shown in Scheme 3 the elimination of the acyloxy moiety results in an energetically favored extension in conjugation of the π-system of the heterocyclic