Monotype

Icacinaceae are a moderate-sized, primarily tropical family consisting of 52 genera, many of which are monotypic, and 300 species. Additional background on taxonomic problems surrounding the family can be found in the 1991 paper by Kaplan et al. Chemical data have been used by Dahlgren (1980) to assess these relationships with related families, but the application involved simple presence or absence data (iridoids) and did not touch upon the dynamic nature of the pathways involved. 

Pterolactam (48) was isolated from bracken (Pteridium aquilinum Kuhn), a fern belonging to a monotypic genus (86). Its IR spectrum strongly resembles the IR spectrum of 2-pyrrolidone the structure of 48 was established by 1H-NMR spectroscopy. It is interesting to note that 48 possesses a weak but definitive optical rotation ([a]D —2.0°). 

Peripentadenia is a monotypic genus of the family Elaeocarpaceae represented by Peripentadenia mearsii (C. T. White) L. S. Smith, a tree growing in rain forests of northern Queensland. Besides unidentified minor alkaloids, the species yields one major alkaloid, peripentadenine (49) (87). Its molecular formula, C22H34N203, was established by high-resolution mass spectroscopy the presence of phenol, ketone, secondary amide, and tertiary amine functionalities was deduced from examination of spectroscopic data. 

Tailoring of Polymer Surfaces with Monotype Functional Groups of Variable Density Using Chemical and Plasma Chemical Processes... 

A more complicated but very variable process (iii) was the pulsed plasma-initiated polymerization or copolymerization. Here, the desired monotype functional groups are provided by the monomer, which are polymerized in the pulsed plasma. The art in producing such 50 nm thick monotype functionalized polymer coatings lays in carrying out the plasma process under as mild conditions as possible to avoid fragmentation of monomers and to preserve and remain the functional groups of the respective monomers. 

It should be remarked that the plasma surface functionalization by oxygen plasma with and without reduction to monotype OH functional groups yields a lower peel strength compared to the use of the monotype functional groups bearing adhesion-promoting plasmapolymer layers (cf. Fig. 11). 

Figure 1 Diatoms are one of the most abundant biota containing siliceous skeletal material in the marine environment. Radiolaria, silicoflagellates, and siliceous sponges also deposit this amorphous phase for structural support. The diatoms in the figure (Corethron sp.) were collected from the Antarctic continental shelf, occurring as a monotypic assemblage in a large phytoplankton bloom. The siliceous frustules in this figure t3fpically are 100-...

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