2- -3-ethyl-5-mcthyl

C kH,xO 3247-97-2) sec Amitriptyline l-cycIopropyl-6-fluoro-l,4-dihydro-5-mcthyl-7-(3-methyK l-piperazinyl)-4-oxo-3 quinolinecarboxylic acid ethyl ester... 

Compound 7-ethyl-7-methyl-3-phenyl-2,3,4,9-tetrahydropyrimido[l,2-tf][l,3,5]triazine-6,8-dione 71 <2002JHC663> was prepared by the one-pot condensation reaction of 6-amino-3-cthyl-3-mcthyl-5//-pyndinc-2,4-dionc 70 with aromatic amines and formaldehyde (Equation 3). 

Several attempts have been made to superimpose creep and stress-relaxation data obtained at different temperatures on styrcne-butadiene-styrene block polymers. Shen and Kaelble (258) found that Williams-Landel-Ferry (WLF) (27) shift factors held around each of the glass transition temperatures of the polystyrene and the poly butadiene, but at intermediate temperatures a different type of shift factor had to be used to make a master curve. However, on very similar block polymers, Lim et ai. (25 )) found that a WLF shift factor held only below 15°C in the region between the glass transitions, and at higher temperatures an Arrhenius type of shift factor held. The reason for this difference in the shift factors is not known. Master curves have been made from creep and stress-relaxation data on partially miscible graft polymers of poly(ethyl acrylate) and poly(mcthyl methacrylate) (260). WLF shift factors held approximately, but the master curves covered 20 to 25 decades of time rather than the 10 to 15 decades for normal one-phase polymers. 

Figure 18. Enantiomer separation of Q 2-1-mcthyl-2-(l-methylethenyl)cyclobutyl]ethyl trifluoroacetate (grandisol) and 2-chloroalkanes on heptakis(2,3,6-tri-0-pcntyl)- -cyclodextrin (42 m glass capillary column, 50 1 bar hydrogen)174.

In contrast, when a twofold excess of the dialkoxydihydropyrazine is used, then 2 1 adducts are obtained. This has been demonstrated18 by reacting A,7V-bis(2-iodoethyl)-4-methylben-zenesulfonamide with two equivalents of the lithiated D-valine/alanine-based dialkoxydihydropyrazine 8 to give 7V.fV-bis 2-[(2S,57 )-2,5-dihydro-5-isopropyl-3,6-dimethoxy-2-mcthyl-2-pyrazinyl]ethyl -4-methylbenzenesulfonamide (9) in high yield and >95% de. The adduct can be hydrolyzed in high yield to the corresponding amino acid methyl ester 10. 

Ethyl-3-(2-methyl-propyl)-sydnon Eine Losung von 1,98 g (10 mmol) 4-Ethyl-3-(2-mcthyl-propyl)-N-nitroso-sydnon-imin in 7 ml Dimethylformamid wird auf dem kochenden Wasserbad bis zur vollstandigen Entfarbung ( 10 min) erwarmt. Das Losungsmittel wird i. Vak. entfernt und das Rohprodukt aus Diethylether umkristallisicrt Ausbeute 1,67 g (98%) Schmp. 45 46". 

---