Alkaloids ofHypecoum erectum, the structure of hyperectine

C19 Benzylisoquinoline Alkaloid with Unprecedented Architecture from Hypecoum erectum

“…Since compound 1 features an unprecedented C19 BIA skeleton, a biosynthetic pathway of 1 together with two coisolates was proposed (Scheme ). As mentioned above, the normal C 16 BIAs (such as armepavine) are synthesized by condensation of dopamine and 4-hydroxyphenylacetaldehyde, which could be both derived from l -tyrosine. , With the key involvement of berberine bridge enzyme, − C 16 BIAs could be transformed to C 17 BIAs, such as epiberberine and N -methylsinactine. , Stevens rearrangement of a tetrahydroprotoberberine N -methyl salt precursor ( N -methylsinactine) would produce C 17 spiro-BIA, − such as sibiricine. , The C 17 spiro-BIA derivative is attacked by asparagine and through dehydration and dehydrogenation could produce rare C 21 spiro-BIA, such as hyperectine . The sibiricine analogue may undergo enzymatic reduction and ring-opening reaction to produce a benzaldehyde derivative.…”

“…19,31 The C 17 spiro-BIA derivative is attacked by asparagine and through dehydration and dehydrogenation could produce rare C 21 spiro-BIA, such as hyperectine. 32 The sibiricine analogue may undergo enzymatic reduction and ring-opening reaction to produce a benzaldehyde derivative. The aldehyde group is attacked by a ketonic acid, such as malonamic acid, and the resulting intermediate could undergo decarboxylation and intramolecular cyclization to give 1 with chiral and racemic features.…”

Ligiamycins A and B, Decalin-Amino-Maleimides from the Co-Culture of Streptomyces sp. and Achromobacter sp. Isolated from the Marine Wharf Roach, Ligia exotica

“…The amino-maleimide substructure is extremely rare in nature. The only previously reported natural products with this moiety are hyperectine and isohyperectine from the plants Hypecoum erectum and Hypecoum leptocapum [29][30][31]. Therefore, ligiamycins A (1) and B (2) are the first amino-maleimide-bearing compounds from microorganisms.…”

β-Phenylethylamines and the isoquinoline alkaloids

“…'57 The two phenanthrene derivatives (1 28) and (1 29), which were originally identified as trace impurities in samples of heroin, have been prepared by heating thebaine with acetic anhydride; they presumably arise from (1 30) by the alternative migrations shown.' s 8 The 2,3-epoxypropyl ether of thebaol (131) has been produced by heating either thebaine or its N-propyl quaternary salt with epichlorohydrin. 5 9 This type of degradation has only previously been reported to occur if quaternary salts are heated with acetic anhydride.…”