Darmstoff analogues. 2. Ring and side-chain effects on smooth-muscle contraction

Area of Science:

• Biochemistry
• Organic Chemistry
• Pharmacology

Background:

• 2-cis-delta 8-Heptadecenyl-4-(hydroxymethyl)-1,3-dioxolane monosodium phosphate (1b) is a major component of mammalian intestinal Darmstoff.
• Darmstoff (1b) is a potent inducer of intestinal smooth muscle contraction.
• An analogous compound, 2-pentadecyl material (1a), is inactive despite being abundant in the intestine.

Purpose of the Study:

• To synthesize novel phosphorylated hydroxymethyl-1,4-dioxanes, -tetrahydrofurans, -cyclopentanes, and -oxathiolanes.
• To evaluate the biological activity of these synthesized compounds, focusing on intestinal smooth muscle contraction.
• To elucidate the specific chemical requirements for Darmstoff-like activity.

Main Methods:

• Synthesis of various cyclic ethers and oxathiolanes with oleyl and palmityl side chains.
• Phosphorylation of the synthesized compounds to yield monosodium phosphate derivatives.
• Assay of intestinal smooth muscle contraction induction for the synthesized compounds.

Main Results:

• 2-(hydroxymethyl)-5-cis-delta 8-heptadecenyl-1,4-dioxane monosodium phosphate (2b) showed approximately 12% of the activity of Darmstoff (1b).
• The pentadecyl analogue (2a) was inactive, similar to its counterpart (1a).
• All other synthesized compounds were found to be inactive.

Conclusions:

• Darmstoff-like compounds require specific chemical structures to exhibit biological activity.
• The observed side-chain specificity for activity, as seen in compounds 1a and 1b, is preserved in the newly synthesized analogues.
• Structural modifications significantly impact the ability to induce intestinal smooth muscle contraction.