Terpenes and Related Compounds. IX

Some studies in the biosynthesis of terpenes and related compounds.

Cyclic terpenes as a class of natural products display a bewildering array of structural types. Well over a hundred different carbon frameworks have been detected so far, many new substances are being currently added to an already impressive list of compounds, and even several representatives of the long-sought group of sesterterpenes have at last made their appearance on the chemical scene14. ...

Studies on the crystalline lens. IX. Quantitative analysis of free amino acids and related compounds.

The concentration of all free amino acids and many related compounds in the lens of rabbits has been determined by ion exchange chromatography, and the concentration of the amino acids in the lens has been compared with those found in a previous study in aqueous and. vitreous humors. The concentration of every free amino acid in the lens was shoiun to be higher than in the aqueous of the poster...

Coumarins, Xanthones and Related Compounds.

It has long been known that coumarins (α-pyrones) and xanthones (γ-pyrones) together form a large class of naturally occurring compounds exhibiting a wide range of biological activities. However, the interest of the scientific community for these secondary metabolites, as well as for their structural analogues, has never decreased since these “old compounds” are constantly generating promising—...

Pteroylglutamic acid and related compounds.

8ƒ¿-hydroxyflavinmononucleotide and Related Compounds

2•L,3•L,4•L-Triacetyl-FMN has been transformed by selec tive radical bromination into 2•L,3•L,4•L-triacetyl-8ƒ¿-bromo-FMN, and the following hydrolysis of the latter has afforded 8ƒ¿-hydroxy-FMN. The presence of the hydroxy group in the 8ƒ¿ position of 8ƒ¿-hydroxy FMN is confirmed by its acetylation into 2•L,3•L-dracetyl-8ƒ¿-acetoxyribofla vin-4•L,5•L-cyclophosphate. The absorption spectra of t...