Formyl iodide synthesis

A highly modified methyl testosterone derivative also exhibits antiandrogenic activity. One synthesis of this compound Involves initial alkylation of methyl testosterone (3 ) by means of strong base and methyl iodide to afford the 4,4-dimethyl derivative Formylation with alkoxide and... 

The synthesis reported by Bonjoch and co-workers utilizes a Ni-mediated reductive cyclization of vinyl iodide 82 with concomitant reductive indolenine formation quenching of the presumed intermediate (dehydrotubifoline, 83) with the Vilsmeier reagent affords A-formyl derivative 84 [36b]. Photoisomerization gives norfluorocurarine (22) in low yield. Similarly, Rawal and He produce... 

The first total synthesis of chiral cherylline (55), a rare phenolic Amaryllidaceae alkaloid, has been fully described.31 Resolution of the previously synthesized ( )-phenethylamine (53) with (—)-diacetone-2-keto-L-gulonic acid gave the (2RH+)- and (2S)-( — )-L-gulonate salts, which were transformed into the diastereomeric hydrobromides the latter were formylated, subjected to Bischler-Napieralski cyclization conditions, and debenzylated to yield the (4R)-(+)-and (4S)-(—)-dihydroisoquinoline (54) hydrochlorides. These were separately selectively O-demethylated, quaternized with methyl iodide, and reduced with... 

A three-step synthesis of cerpegin (118) was described by Hong and Comina (235). Lithiation of 2-methoxypyridine (361) with mesityllithium followed by the addition of N-formyl-A/,lV, 7V -trimethylethylenediamine (362) gave an a-amino alkoxide which was treated with n-butyl lithium. The resulting dianion 363 was reacted with cerium chloride followed by acetone to yield, after acidification, the lactol 364. Oxidation with PCC gave 365, which was treated with methyl iodide at 145°C to afford 118 (Scheme 43) (235). The overall yield was 34%. 

Condensation of syn- or anti-27 with hydrazine afforded new pyrazole derivatives 28 with a stereodefined and protected amino diol side chain [64]. The preparation of push-pull substituted unsaturated monosaccharide derivatives and their use in the synthesis of nucleoside analogs have been reviewed [65]. Thus, the 2-formyl pentose glycals were transformed to the corresponding acyclo-C-nucleosides 29 [66]. Similarly, the benzy-lated 2-formylglycals reacted with hydrazine derivatives to afford the substituted l,2,4-tri-0-benzyl-lC-(lH-pyrazol-4-yl)-D-tetritols the deprotection of which was achieved with Pd/H2 to yield the lC-( 1-methyl-lH-pyrazol-4-yl)-D-tetritols [67]. 3-0-Benzyl-6-deoxy-l,2-0-isopropylidene-o -D-xylo-hept-5-ulofuranurono-nitrile was reacted with f, N-dimethylformamide dimethyl-acetal in THF to furnish the (E)-3-0-benzyl-6-deoxy-6-dimethyl-aminometh-ylene-l,2-0-isopropylidene-Q -D-xylo-hept-5-ulofuranurono-nitrile as a major product, and on treatment with carbon disulfide and methyl iodide under basic conditions afforded 3-0-benzyl-6-deoxy-l,2-0-isopropylidene-6-[bis(methylsulfanyl)methylene]-a-D-xylo-hept-5-ulofuranurono-nitrile. Further reaction with hydrazines yielded the reversed pyrazole-C-nucleoside analogs [68]. 

The desired glycan derivative 66 was accessed by performing a nucleobase elimination on the TlPS-protected D-thymidine. " The synthesis ccmtinued with the formylation of 66 followed by reduction to give the primary alcohol 67. Conversion of the alcohol to the halide provided the iodide 64, which was coupled to pyrrole 40 (Scheme 23). ... 

Bcnzo[b]selenoph is and thdr Benzo-fused Derivatives.— The oxo-derivative (511) is a key intermediate in the synthesis of benzo[b]selenophens. Through reduction with sodium borohydride the parent compound is obtained, while reaction with methyl magnesium iodide yields the 3-methyl derivative. Under Vilsmeier formylation conditions, (511) was transformed into 3-chloro-2-formylbenzo[b]selenophen, a useful compound for the fusion of further rings. Compound (511) can also be condensed with aromatic aldehydes to compounds (512), some of them with antibacterial... 

---