856906-43-9

Upstream product

• 196081-71-7 2-bromo-3-hydroxy-benzaldehyde 
• 100-39-0 benzyl bromide 
• 75-16-1 methylmagnesium bromide 
• 158584-99-7 3-(benzyloxy)-2-bromobenzaldehyde 
• 870288-28-1 1-(3-benzyloxy-2-bromo-phenyl)-ethanol 

Downstream Products

• 856906-44-0 2-(3-benzyloxy-2-bromo-phenyl)-2-methyl-oxirane 

Relevant academic research and scientific papers

Metal-free visible light-promoted synthesis of isothiazoles: A catalytic approach for N-S bond formation from iminyl radicals under batch and flow conditions

A sustainable synthesis of isothiazoles has been developed using an α-amino-oxy acid auxiliary and applying photoredox catalysis. This simple strategy features mild conditions, broad scope and wide functional group tolerance representing a new enviromenta

PENTACYCLINE DERIVATIVES FOR THE TREATMENT OF INFECTIONS

The tetracycline class of antibiotics has played a major role in the treatment of infectious diseases for the past 50 years. However, the increased use of the tetracyclines in human and veterinary medicine has led to resistance among many organisms previously susceptible to tetracycline antibiotics. The modular synthesis of tetracyclines and tetracycline analogs described provides an efficient and enantioselective route to a variety of tetracycline analogs and polycyclines previously inaccessible via earlier tetra-cycline syntheses and semi-synthetic methods. These analogs may be used as anti-microbial agents or anti-pro liferative agents in the treatment of diseases of humans or other animals.

Synthesis of (-)-tetracycline

We describe a convergent, enantioselective synthesis of (-)-tetracycline (1) from benzoic acid (17 steps, 1.1% yield). Benzoic acid was transformed into the AB precursor 2 in 10 steps (11% yield), as previously described, and the latter compound was activated toward Diels-Alder cycloaddition by the introduction of an α-phenylthio group (two steps, 66% yield). Heating of the resulting α-(phenylthio)enone (3) with the triethylsilyloxybenzocyclobutene derivative 4 at 85 °C gave the endo-Diels Alder adduct 5 in 64% yield. Deprotection and oxidation of the latter intermediate gave the 2-(phenylthio)-1,3-diketone 7, which was oxidized with m-chloroperoxybenzoic acid in the presence of trifluoroacetic acid. The sulfoxide intermediate(s) formed eliminated upon warming to 35 °C to give the anyhydrotetracycline derivative 8. Intermediate 8 underwent spontaneous autoxidation at 23 °C to form the hydroperoxide keto-9 stereoselectively. Without isolation, hydrogenolysis of 9 in the presence of palladium black gave (-)-tetracycline (42% yield from 7), indistinguishable from an authentic sample. Copyright

SYNTHESIS OF TETRACYCLINES AND ANALOGUES THEREOF

The tetracycline class of antibiotics has played a major role in the treatment of infectious diseases for the past 50 years. However, the increased use of the tetracyclines in human and veterinary medicine has led to resistance among many organisms previously susceptible to tetracycline antibiotics. The modular synthesis of tetracyclines and tetracycline analogs described provides an efficient and enantioselective route to a variety of tetracycline analogs and polycyclines previously inaccessible via earlier tetracycline syntheses and semi-synthetic methods. These analogs may be used as anti-microbial agents or anti-proliferative agents in the treatment of diseases of humans or other animals.