Sterols from the fungus Catathelasma imperiale

Abstract

Eight ergostane-type sterols and three their derivatives (one mono-linoleate and two mono-glucosides) were isolated from the ethyl acetate soluble fraction of the fungus Catahelasma hperinle . Two of them are novel compounds, namely 22E. 24R-ergosta-7,22-diene-3fl,5a-dio1-6~-linoleate (1) and 22E ,24R-ergosta-7,22-diene-38, Sfl , 6a -trio1 ( 5 ) with an uncommon c tfused A/B ring. Structures of these compounds were demonstrated on the basis of their chemical evidences and spectroscopic methods, especially 2D NMR techniques.

Investigation of solid mixing mechanisms in a bubbling fluidized bed using a DEM—CFD approach

“…The common of these investigations is that they are carried out either in small beds or at low fluidizing velocity. The works by Niklasson et al ,12 Schlichthaerle and Werther,29 Xiao et al ,30 and Yang et al ,31 which are carried out in relative large beds and at high fluidizing velocity, report that the values of D sr are around 0.1 m 2 /s.…”

Lateral solids dispersion coefficient in large-scale fluidized beds

“…8, several other correlations [8,12,19] are also tried. But, finally the correlation proposed by Borodulya et al is selected, because it considers the effect of bed width.…”

“…Here, such a review on the values of D sr is updated. A list of experimental studies [6][7][8][9][10][11][12][13][14][15][16][17][18][19] with measurement conditions and results is collected (see the supplementary materials, listed in a table). More than a dozen of works altogether since 1980s are collected.…”

Pentanol derivatives from basidiomycete Catathelasma imperiale and their 11β-hydroxysteroid dehydrogenases inhibitory activity

“…The above NMR character allowed us to conclude that 3 was a diacetylated pentanediol containing a keto group. By analysis of the HMBC spectrum (Figure 1), the position of the ketone was determined at C-2, in which the correlations from H-1 to C-3 and C-a 1 , from H-5 to C-3 and C-b 1 and from H-4 to C-2 were observed. Therefore, the structure of 3 was elucidated as 2-oxopentane-1,5-diyl diacetate named catathelasmol C, which was a new natural product.…”

“…Only a few ergosterols have been reported from the chemical investigation of this fungus. 1 As a part of our efforts to discover the structurally diverse and biologically active secondary metabolites from higher fungi, 2-5 the investigation of the fruiting bodies of C. imperiale has led to the isolation of five new compounds, catathelasmols A-E (1)(2)(3)(4)(5). Herein, details of the isolation and structural elucidation of 1-5 are described, including assignment of the absolute configurations by computational chemistry.…”