Norlobariol methyl ester

The objective of this work is to evaluate methyl ester alginates and alginic acid (AA) as moisture-scavenging excipients for the formulation of aspirin tablets obtained by direct compression. The tablets were stored at accelerated conditions (40 °C/75 % RH) and assessed for changes in tensile strength, mass, thickness and disintegration time. While moisture caused a reduction in the hardness of MCC and AA tablets, hardness of the tablets made from methylated materials was virtually unaffected. The physical stability of alginate ester tablets was found to be related to their increased plastic deformation leading to extended interparticle contact with less impact on tablet porosity. Finally, the combination of higher moisture affinity and lower water dissociation exhibited by alginates esters resulted in tablets with the lowest aspirin degradation. These findings suggest that excipients with high water retention can act as moisture-scavengers without losing their functional properties and reducing the degradation of moisture-sensitive drugs.

Fatty acid methyl ester (FAME) analyses can be useful for distinguishing microbial species. This study conducted FAME analyses on 14 fungal species known to cause grapevine trunk diseases. FAME profiles were dominated by oleic acid, albeit profiles were characteristic enough to separate species. Discriminant analyses suggested that palmitoleic acid/sapienic acid, pentadecylic acid, and an unsaturated 17-carbon fatty acid (17:1ω8 c)could explain 79.8% of the variance in the profiles among species in the first three discriminant functions. FAME profile libraries were created for use in a commercialized software, which was able to accurately identify isolates to the species level, with a low rate (9.4%) of samples to be reassessed. Dendrograms created using neighbor-joining cluster analyses with data from FAME profiles were compared with those using internal transcribed spacer (ITS) region sequences. This revealed that FAME profiles, albeit useful for tentative species identification, should not be used for determining phylogenetic relationships because the dendrograms were significantly unconcordant. Regardless, these results demonstrated the potential of FAME analyses in quickly and initially identifying closely related fungal species or confirming conclusions from other species identification techniques that would require independent validation.

The clinically used DNA-alkylating drug streptozotocin (STZ) was investigated using a simple work-up as an O-methylating agent to transform various carboxylic acids, sulfonic acids and phosphorous acids into corresponding methyl esters, and did so with yields of up to 97% in 4 h at room temperature. Good substrate tolerance was observed, and benefited from the mild conditions and compatibility of the reaction with water.