281190-95-2

Upstream product

• 1449761-11-8 tert-butyl 2-(diphenylmethyleneamino)-3-(4-methoxyphenyl)propanoate 
• 65806-89-5 (R)-2-{[(benzyloxy)carbonyl]amino}-3-(4-methoxyphenyl)propionic acid 
• 64205-12-5 N-α-benzyloxycarbonyl-D-tyrosine 
• 728944-91-0 (R)-tert-butyl 2-{[(benzyloxy)carbonyl]amino}-3-(4-methoxyphenyl)propionate 

Downstream Products

• 281191-01-3 (2R,2'E,5'S,6'R,7'E)-tert-butyl 3-(4-methoxyphenyl)-2-({6'-methyl-8'-phenyl-5'-[(triisopropylsilanyl)oxy]octa-2',7'-dienoyl}amino)propionate 
• 642087-19-2 2-[2-(diethoxy-phosphoryl)-acetylamino]-3-(4-methoxy-phenyl)-propionic acid tert-butyl ester 
• 155645-51-5 Cryptophycin 4 
• 162473-78-1 desepoxyarenastatin A 
• 162600-54-6 cryptophycin-24 
• 728944-93-2 (2S,1''S,2''R,1''''R)-1''-[3'''-({1''''-[(tert-butoxy)carbonyl]-2''''-(p-methoxyphenyl)ethyl}carbamoyl)allyl]-2''-methyl-4''-phenylbut-3''-enyl 2-[(3'-{[(tert-butoxy)carbonyl]amino}propionyl)oxy]-4-methylpentanoate 
• 186256-66-6 cryptophycin-51 
• 186256-67-7 cryptophycin 52 
• 186256-68-8 cryptophycin 53 
• 642087-13-6 3-(diethoxyphosphinyl)-N-(3-chloro-4-methoxyphenyl)-D-alanine tert-butyl ester 
• 642087-17-0 3-(3-chloro-4-methoxyphenyl)-(2R)-2-((5S,6R)-5-hydroxy-6-methyl-8-phenyl-octa-2(E),7(E)-dienoylamino)propionic acid tert-butyl ester 
• 186193-12-4 (S)-2-(3-Amino-2,2-dimethyl-propionyloxy)-4-methyl-pentanoic acid (E)-(1S,2R)-1-{(E)-3-[(R)-1-carboxy-2-(3-chloro-4-methoxy-phenyl)-ethylcarbamoyl]-allyl}-2-methyl-4-phenyl-but-3-enyl ester 
• 642087-18-1 (2S)-2-(3-tert-butoxycarbonylamino-2,2-dimethyl-propionyloxy)-4-methyl-pentanoic acid (1S,2R,2E)-1-{3-[1-tert-butoxycarbonyl-(2R)-2-(3-chloro-4-methoxyphenyl)ethylcarbamoyl]allyl}-2-methyl-4-phenyl-but-(3E)-enyl ester 
• 162465-18-1 (S)-2-((R)-3-Amino-2-methyl-propionyloxy)-4-methyl-pentanoic acid (E)-(1S,2R)-1-{(E)-3-[(R)-1-carboxy-2-(4-methoxy-phenyl)-ethylcarbamoyl]-allyl}-2-methyl-4-phenyl-but-3-enyl ester 

Relevant academic research and scientific papers

Recoverable Dendritic Phase-Transfer Catalysts that Contain (+)-Cinchonine-Derived Ammonium Salts

Four new phosphorus dendrimeric phase-transfer catalysts are prepared that contain 12 (+)-cinchoninium salts on the surface obtained by the quaternisation of the quinuclidinic N atom. The asymmetric alkylation of a glycinate Schiff base with benzyl bromide is used as a benchmark reaction, and the dendrimeric catalyst that contains an allyl group on the O-9 hydroxy group of the cinchonine units is the most active. The recovery and reuse of the catalyst are possible for five consecutive runs without loss of activity and with only a slight decrease in enantioselectivity. If other electrophiles are used, substituted benzyl bromides give better results than other activated alkyl bromides to afford the corresponding R amino acid derivatives. A comparison of these results with those reported previously for similar cinchoninium salts shows that dendrimers could be a better support than other polymers for this type of organocatalysis.

Asymmetric syntheses of potent antitumor macrolides cryptophycin B and arenastatin A

Efficient and highly stereoselective syntheses of cryptophycin B and arenastatin A, potent cytotoxic agents, are described. An ester-derived titanium enolate mediated syn-aldol reaction was employed to generate the stereocenters C-5 and C-6. The route is convergent and provides a convenient access to the synthesis of structural variants of cryptophycins as well as members of its family. ( Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004).

A convergent synthesis of (+)-cryptophycin B, a potent antitumor macrolide from Nostoc sp. cyanobacteria.

[structure--see text] An efficient and highly stereoselective synthesis of cryptophycin B (2), a potent cytotoxic agent, is described. The ester-derived titanium-enolate-mediated syn-aldol reaction was employed to generate the stereocenters C(5) and C(6). The route is convergent and provides a convenient access to the synthesis of structural variants of cryptophycin B as well as members of its family.