70600-49-6

Upstream product

• 70600-64-5 trimethyl[(E)-non-3-en-1-ynyl]silane 
• 89942-12-1 (E)/(Z)-1-bromo-1-heptene 
• 628-71-7 1-Heptyne 
• 60595-37-1 (E)-1-iodohept-1-ene 
• 2548-87-0 (E)-2-Octenal 
• 54542-97-1 (E)-1-heptenyldiisobutylaluminium 
• 42474-21-5 1,2-dibromoheptane 
• 592-76-7 1-Heptene 
• 460-12-8 Butadiyne 
• 693-25-4 n-pentylmagnesium bromide 

Relevant academic research and scientific papers

Studies towards the total synthesis of Phostriecin

A synthetic approach toward the phostriecin, an antitumor natural product is described. The key features of the present synthesis are Wittig reaction, synthesis of homoallylic alcohol using Brown's protocol (alkoxyallylboration) and RCM for the creation of unsaturated lactone moiety of phostriecin.

PREFERENTIAL FORMATION OF 8-EPI-PROSTAGLANDIN F2Sa VIA THE CORRESPONDING ENDOPEROXIDE BY A BIOMIMETIC CYCLIZATION

Homolytic demercuration of the 1,2-dioxolanes 14a and 14b in the presence of oxygen leads preferentially to endoperoxide 17 (both epimers at C*) which upon reduction affords 8-epi-prostaglandin F2α and the C(15)-epimer, a result in accord with a previous mechanistic proposal.

Structure-Proving Syntheses of the Polyenoyltetramic Acids Pyranonigrin J and I

The polyenoyltetramic acids pyranonigrin J (3) and pyranonigrin I (4) had been isolated from Aspergillus niger. Their origins from and roles in biosynthesis as well as the S-configurations of their stereocenter had been deduced from expression experiments with modifications of the corresponding gene cluster. We corroborated this stereochemical assignment after executing the first total syntheses of both compounds because they had essentially the same specific rotations as their natural counterparts. Our syntheses used the β-ketothioester 18 as a conjunctive reagent. It was combined with the l-serine derivatives (S)-19 or (S)-21 (“Western building blocks”), respectively, through aminolyses. Stille couplings with the stannane 13 (“Eastern building block”) followed. The resulting β-ketoamides (S)-11 and (S)-12 underwent desilylative Lacey-Dieckmann cyclizations when exposed to 8 equiv. of Bu4NF. They rendered the polyenoyltetramic acids (S)-26 [acidolysis: → (S)-3] and (S)-4, respectively.

HYDROZIRCONATION METHODS FOR NATURAL ISOBUTYLAMIDES (ANACYCLIN, PELLITORINE AND ITS VINYLOGUE) AND SYNTHONS.

Hydrometallation of α,ο-diynes is used to make ο-acetylenic isobutylamide synthons: new syntheses of anacyclin, pellitorine and its vinylogous triene are described.

HIGHLY STEREO- AND REGIOSELECTIVE PALLADIUM-CATALIZED SYNTHESES OF (3E,5Z)-(3E,5E)-,AND (3Z,5E)-1,3,5-UNDECATRIENE

(3E,5Z)-1,3,5-Undecatriene (3) having 98.2percent stereoisomeric purity has been prepared by a new and expeditious route involving two selective Pd-catalyzed carbon-carbon bond forming reactions.The key step of this synthesis is a highly diastereoselective Pd-catalyzed cross-coupling reaction between 1-heptynylzinc chloride (11a) and a molar excess of (E)/(Z)-1,2-dibromoethylene (12). Another highly diastereoselective Pd-catalyzed reaction, which involves a cross-coupling between trimethylsilylethynylzinc chloride (15) and molar excesses of stereoisomeric mixtures of 1-bromo-1-alkenes (16), has been used to prepare (E)-1-trimethylsilyl-3-nonen-1-yne (10a), a key intermediate for the synthesis of (3E,5E)- and (3Z,5E)-undecatriene, (4) and (5).Compounds 3 and 4, isolated from the essential oil of Ferula galbaniflua, also occur together with compound 5 in the male attracting oils of seaweeds.These substances have odors highly appreciated in perfumery.

A study of the reactions of 1,3-diynes with organo-cuprates and -argentates

1,3-Diynes HCC-CC-R' (1, R'= H or Ph) are converted by cuprates M' (R = alkyl; Y = Cl, Br or R; M'= Li, MgCl or MgBr) into a mixture of C-R'>M' (2) and C-R'>M' (3).When R is n-alkyl, adducts 2 are the major pr