Tetracyclin synthesis

Suggest a synthesis for 5-Meo tetralone (1) used for a tetracycline synthesis (see p 431 ). 

Examine the tetracycline synthesis on page 432 Does It follow a linear or convergent strategy ... 

Table 4.28 Summary of reaction metrics and synthesis tree parameters for tetracycline synthesis plan ranked according to overall kernel (maximum) RME. ...

Tebbe reaction 148 Tetracyclin synthesis 190 Tetrazole synthesis 17 Tetrodotoxin synthesis 136 Tocopherol synthesis 142 Tonantzitlolone synthesis 188 Triazine synthesis 17 Triclavulone synthesis 102... 

Review Problem 18 Design a synthesis for TM208, an intermediate in Woodward s tetracycline synthesis (Pure and Applied Chemistry,... 

Some adverse effects of tetracycline. synthesis by the mechanism determined for streptomycin [strep toe... 

One strategy for tetracycline synthesis is to build a B/C precursor with suitable functionality for extension to ring A and with the tertiary a-hydroxy-carbonyl unit already in place. Two potential starting materials for different tetracyclines are 293 and 295 and both might be made by a-hydroxylation of enolates. 

Juglone = 5-hydroxy-l,4-naphthalenedione dienophile in tetracycline synthesis, 318 Julia-Lythgoe olefination, 34 Julia s terpenoid synthesis, 69-70 Juvenile hormone synth. steps, 20, 30, 135, 155... 

The photoreduction of the naphthoquinone methide (19) has been investigated,35 in connection with Barton s use of photocyclization of derivatives of (19) in tetracycline synthesis.3 Hydrogen abstraction by the triplet of (19) from... 

The available options are exemplified in Scheme 3.3 by a multifunctional-ized but simply branched intermediate 15 taken from the tetracycline synthesis of Woodward [1]. Remember to always choose the cut at the branching... 

As in the tetracycline synthesis of Scheme 105 other examples have been reported in which the only cyclized products are the Cy6 ones in the Cy5/Cy6 case involving an unstabilized radical. One of these examples (Scheme 106) was reported by McLean, who explained the by-products formed during the dehydrogenation of lupenyl acetate (256) with mercuric acetate in chloroform-acetic acid solution as deriving from the radical 257 by cyclization to a (Cy 6) radical (258). It must be noted, however, that 258 is both a tertiary and allylic radical. It may also be noted that in all these cases, the situation is similar to the one discussed in Section IV (Scheme 12, Table 2, entries 1,2,7)... 

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