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We previously identified the aur1 gene cluster which produces the angucycline antibiotic auricin. Preliminary characterisation of auricin revealed that it is modified by a single aminodeoxysugar, D-forosamine. Here we characterise the D-forosamine-specific genes. The four close tandem genes, aur1TQSV, encoding enzymes involved in the initial steps of the deoxysugar biosynthesis, were located on a large operon with other core auricin biosynthetic genes. Deleting these genes resulted in the absence of auricin and the production of deglycosylated auricin intermediates. The two final D-forosamine biosynthetic genes, sa59, an NDP-hexose aminotransferase, and sa52, an NDP-aminohexose N-dimethyltransferase, are located in a region rather distant from the core auricin genes. A deletion analysis of these genes confirmed their role in D-forosamine biosynthesis. The Δsa59 mutant had a phenotype similar to that of the cluster deletion mutant, while the Δsa52 mutant produced an auricin with a demethylated D-forosamine. Although auricin contains a single deoxyhexose, two glycosyltransferase genes were found to participate in the attachment of D-forosamine to the auricin aglycon. An analysis of the expression of the D-forosamine biosynthesis genes revealed that the initial D-forosamine biosynthetic genes aur1TQSV are regulated together with the other auricin core genes by the aur1Ap promoter under the control of the auricin-specific activator Aur1P. The expression of the other D-forosamine genes, however, is governed by promoters differentially dependent upon the two SARP family auricin-specific activators Aur1PR3 and Aur1PR4. These promoters contain direct repeats similar to the SARP consensus sequence and are involved in the interaction with both regulators.

A series of 1-glycosylmethyl-4,5-diphenyl-1H-imidazoles with six different glycosyls were obtained in 48-55% yields from the multicomponent reaction of the corresponding C-glycosyl methylamines, formaldehyde, benzil, and ammonium acetate under catalysis with indium(III) chloride in methanol at ambient temperature. Starting with C--D-glucopyranosyl or C--Dgalactopyranosyl methylamines, the procedure also was examined with phenylglyoxal or glyoxal instead of benzil, and the pertinent 1--D-glycopyranosylmethyl-4-phenyl-1Himidazole and -5-phenyl-1H-imidazole or 1--D-glycopyranosylmethyl-1H-imidazole derivatives were prepared and isolated. Of four differently 4-and 5-substituted 1-(-Dglucopyranosylmethyl)-1H-imidazoles, only the 5-phenyl derivative exhibited a weak inhibition of rabbit muscle glycogen phosphorylase b (IC 50 = 125 μM).

Two lipases, Novozyme 435 (lipase B from Candida Antarctica) and Lipozyme TL IM (Thermomyces lanuginosus) were used successfully for the kinetic resolution of racemic 1-(2-furyl)-3-pentanol, the key intermediate in synthesis of the bark beetle pheromone, chalcogran. The desired S-(+)-enantiomer was prepared in enantiomeric excesses higher than 98 % and with yields of 26.3 % and 32.5 %, respectively. Methyl tert-butyl ether and vinyl acetate were found to be the best reaction media and the acetyl donor to achieve fast and effective resolution.

Phthalocyanines with annelated thiazole rings were synthesised by cyclotetramerisation of benzothiazoledicarbonitriles. Three types of these dicarbonitriles with ortho‐configuration were prepared from disubstituted anilines and their cyclisation led to all possible patterns of annelation in the phthalocyanine skeleton. Further substitution at the periphery of the macrocycle by methyl or tert‐butyl substituents was realised to improve the solubility or to allow further derivatisation of target molecules. The characteristic UV/Vis spectral Q‐bands were shifted to higher wavelengths (712–729 nm) because of the higher delocalisation, and fluorescence quantum yields increased compared with isoelectronic naphthalocyanines. Aggregation properties of the studied phthalocyanines were dependent on the type of isomer. The effects of the annelation pattern on the redox potentials were also investigated. Experimental data are compared with theoretical values obtained by DFT calculations.

Activated enol ethers derived from methyl or ethyl acetoacetate/cyanoacetates or nitriles and pentane-2,4-dione react with pentafluorophenylhydrazine through the primary amino-group to afford pyrazoles bearing a preferred 5-amino-over 5-methyl-or 5-hydroxy-substituent in the resulting 4-substituted pyrazoles.

A simple protocol allows the four component condensation of six different C‐glycosyl methylamines, 1,2‐diketones, formaldehyde, and ammonium acetate to give imidazole substituted products such as (IV).