Reference

Analogs Incorporating trans-4-Hydroxy-L-proline That Reverse Multidrug Resistance Better than Hapalosin

Analogs Incorporating trans-4-Hydroxy-L-proline That Reverse Multidrug Resistance Better than Hapalosin. Dinh, Tam Q.; Smith, Charles D. 187479-10-3 are also occured in this study.; Armstrong, Robert W. (Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095, USA). Journal of Organic Chemistry, 62(4), 790-791 (English) 1997 American Chemical Society. CODEN: JOCEAH. ISSN: 0022-3263. DOCUMENT TYPE: Journal CA Section: 34 (Amino Acids, Peptides, and Proteins) Section cross-reference(s): 1 Hydroxyproline-contg. hapalosin analogs I [R = H, CH2C6H4OMe (PMB); R1 = H, CONHCH2Ph] were prepd. in several steps starting from trans-4-hydroxy-L-proline. Whereas the PMB ether of hapalosin possesses substantially lower lower anti-multidrug resistance activity than hapalosin, analogs I (R = PMB, R1 = H; R = H, R1 = CONHCH2Ph) reverse multidrug resistance better than hapalosin, while I (R = = R1 = H; R = PMB, R1 = CONHCH2Ph) were less effective that hapalosin. These results suggest that a free hydroxyl and an arom. group may be important in the multidrug resistance activity of hapalosin and its analogs. .

Heterocyclic

Heterocyclic .beta.-enamino esters, 19. Pyrrolo[2,3-d]- and pyrrolo[1,2-a]pyrimidines from heterocyclic .beta.-enamino esters or -nitriles and isocyanates and acetylacetone. Wamhoff, Heinrich; Wehling, Bernhard (Inst. Org. Chem. Biochem., Univ. Bonn, Bonn, Ger.). Chem. Ber., 109(9), 2983-95 (German) 1976. CODEN: CHBEAM. DOCUMENT TYPE: Journal CA Section: 28 (Heterocyclic Compounds (More Than One Hetero Atom)) Pyrrolopyrimidines I (R = Ph, CH2Ph, CH2OMe, R1 = tosyl; R = CH2Ph, R1 = H), II (R = CH2Ph, R1 = H), III (R = CH2Ph, CH2OMe, Me; R2 = Me; R3 = H) and III (R = CH2Ph, R2 = cyano, R3 = SH) were prepd. in 47-91% yields by cyclizing enamino esters IV (R1 = tosyl, R2 = R3 = H, R4 = CO2Me), or V (R1 = R3 = H, R2 = R4 = CO2Et) (VI) or enamino nitriles V (R1 = R3 = H, R2 = Me, R4 = cyano)(VII) or V (R1 = H, R2 = R4 = cyano, R3 = SH) with RNCO. Excess isocyanate often gave multiple addn. at the 1- and 5-positions to give 44, 17, and 72% VIII [R1 = R3 = CONHCH2Ph, R2 = R4 = CO2Et, R6 = NHCONHCH2Ph; R1 = H, R2 = Me, R3 = CONHCH, Ph, R4 = cyano, R6 = N(CONHCH2Ph)2; or R1 = H, R2 = R4 = cyano, R3 = SC(O)NHCH2Ph, R6 = NHCONHCH2Ph], resp.There are some commonly used reagents with their cas registry numbers 61078-91-9 and 3173-56-6 in this article., but these substituents were smoothly removed during alk. ring closure. Steric and electronic effects of the 3-substituent inhibit isocyanate addn. to the 2-NH2 group. MeNCO added to V (R1 = R3 = H, R2 = Me, R4 = cyano)[ in a 3:1 ratio to give 34% VIII [R1 = CONHMe, R2 = Me, R3 = H, R4 = cyano, R6 = N(CONHMe)2] which was cyclized by base to give 36% pyrrolotriazine IX. V (R1 = R3 = H, R2 = Me, R4 = CO2CMe3) VI, or VII cyclized with (MeCO)2CH2 to give 50-62% pyrrolopyrimidines X. .