Amide-transforming activity of Streptomyces: possible application to the formation of hydroxy amides and aminoalcohols

Abstract

To develop an efficient bioconversion process for amides, we screened our collection of Streptomyces strains, mostly obtained from soil, for effective transformers. Five strains, including the SY007 (NBRC 109343) and SY435 (NBRC 109344) of Streptomyces sp., exhibited marked conversion activities from the approximately 700 strains analyzed. These strains transformed diverse amide compounds such as N-acetyltetrahydroquinoline, N-benzoylpyrrolidine, and N-benzoylpiperidine into alcohols or N,O-acetals with high activity and regioselectivity. N,O-acetal was transformed into alcohol by serial tautomerization and reduction reactions. As such, Streptomyces spp. can potentially be used for the efficient preparation of hydroxy amides and aminoalcohols.

Visible Light Mediated Chemoselective Hydroxylation of Benzylic Methylenes

“…1 H NMR (400 MHz, DMSO): δ 11.98 (s, 1H), 8.31 (dd, J = 5.1, 1.6 Hz, 1H), 7.89 (dd, J = 7.4, 1.3 Hz, 1H), 7.10 (dd, J = 7.4, 5.1 Hz, 1H), 5.40 (dd, J = 7.4, 1.8 Hz, 1H), 4.14 (dd, J = 13.7, 2.0 Hz, 1H), 3.96 (dd, J = 13.7, 7.4 Hz, 1H), 2.58 (s, 3H). 13 1-(4-Hydroxy-3,4-dihydroquinolin-1(2H)-yl) Ethan-1-one (23). 23 The residue was purified by column chromatography (Hex/EA = 1/ 1) on silica gel and collected as white solid (40.2 mg, 70% yield with 91% conversion of raw material).…”

“…13 1-(4-Hydroxy-3,4-dihydroquinolin-1(2H)-yl) Ethan-1-one (23). 23 The residue was purified by column chromatography (Hex/EA = 1/ 1) on silica gel and collected as white solid (40.2 mg, 70% yield with 91% conversion of raw material). mp 103.7 °C.…”

Insights into the Biosynthesis of Cyclic Guanidine Alkaloids from Crambeidae Marine Sponges

“…The transformation of crambescin A into C could arise from an oxidation of the nitrogen into an iminium, followed by hydrolysis into an aldehyde, and a final reduction into a primary alcohol. This transformation is supported by biotransformations of amino derivatives …”

Insights into the Biosynthesis of Cyclic Guanidine Alkaloids from Crambeidae Marine Sponges

“…Subsequent cyclization via at ethered Biginelli condensation [12] would ensure the formation of the central 1aminopyrrolo[1,2-c]pyrimidine (12)a sacentral biosynthetic platform of CGA. Final esterification with diverse guanidinylated alcohols,which may also arise from l-arginine (6)or homoarginine (13), would produce crambescins Aa nd then crambescins C( e.g. crambescin C1-480 (14)) after hydrolysis of the pyrrolinium.…”

“…This transformation is supported by biotransformations of amino derivatives. [13] These two distinct hypotheses prompted us to design the first feeding experiments with labeled precursors on asponge containing CGA ( Figure 2). [2a, 14] Thee ncrusting sponge Crambe crambe (Family:C rambeidae) was selected as an appropriate model to this end as it is widespread in the Western Mediterranean sea, and also well known to produce both crambescins and crambescidins CGA.…”