Activity against the Gram-positive bacterium S aureus proved to be much higher than against the Gram-negative bacterium and fungus(Table 4), Activity against S aureus for the 3-propyl-, 13-butyl-, and 13-hexylberberine (5, 6, and 7)increased as the length of the alkyl chain increased. This is in line with what was previously observed for 13-methyl-, and 13-ethylberberine(2 and 3 )(1). In like fashion, in palmatine analogs tested for the first time, activity against S aureus increased as the length of alkyl chain rose in the order methyl, ethyl, propyl, butyl and hexyl groups. 13-Alkyl derivatives of the berberine-type, with methoxy groups at the same positions (palmatine-type). Activity against S, aureus ATCC 3061(S2) was generally lower than against S aureus X(SI) isolated from hospitalized patients Among the 13-alkyl substituted analogs, 13-hexyl derivatives(7 and 13) displayed the highest activity against all strains. 13-Hexylberberine()showed the best activity against SI and S2, with Impressive 128-fold over paren berberine( 1). Similarly, 13-hexyl palmatine( 13)demonstrated stronger activity against SI and S2 than the parent compound by factors of 128 and 32, respectively Among the 13-alkyl substituted analogs, 13-hexyl derivatives(7 and 13)displayed the highest activity against all strains. 13-Hexylberberine(7)showed the best activity against SI and S2, with an impressive 64- and 128-fold increase over the parent berberine( 1). Similarly, 3-hexylpalmatine (13) compound by factors of 128 and 32, respectively. The activity of 13-hexylberberine against S2 was, in fact, comparable to that of kanamycin ulfate. 13-Hexylberberine(7)and 13-hexylpalmatine(13)showed potent activity against Sl, and proved to be 8 and 4 times, respectively superior to kanamycin sulfate. 13-Hexylberberine(7)and 13-hexylpalmatine(13)showed potent activity against Sl, and proved to be 8 and 4 times, respectively, superior to kanamycin sulfate. 13-Hexylberberine( 7)and 13-hexylpalmatine(13)also showed activity against Candida albicans IFO 1061(MIC 15.6 H g/ml) although kanamycin sulfate was inactive(MIC>2000 g/ml) Only 13-hexylberberine( 7)demonstrated a relatively high activity(MIC250 u g/ml) against E coli IFO 026, even though the activity was only one-eighth of that of kanamycin sulfate. The other 13-alkyl derivatives, except for 13-hexylpalmatine( 13), exhibited weak activity(MIC>1000 H g/ml). 13-Butylberberine(6) and 13-butylpalmatine (12) possessed significant activity against n conclusion, among the tested compounds, 13-hexylberberine(7) and 13-hexylpalmatine(13) were found to be 8 and 4 times, respectively, more active against S aureus(S1)than kanamycin ulfate. 13-Hexylberberine(7)showed high activity against S aureus(S2) comparable to that of kanamycin sulfate. 13-Hexylberberine(7)and 13-hexylpalmatine(13) had very strong activity against Saureus compared with the clinically used alkaloid berberine (1). The 13-hexyl derivatives of berberine and palmatine are highly selective in inhbiting the growth of Gram-positive, S aureus, while they were less potent against the fungus Candida albicans. Their activities were also very low against Gram-negative E coli Further evaluations are required inActivity against the Gram-positive bacterium S.aureus proved to be much higher than against the Gram-negative bacterium and fungus(Table 4),Activity against S.aureus for the 13-propyl-,13-butyl-,and 13-hexylberberine (5,6,and 7)increased as the length of the alkyl chain increased.This is in line with what was previously observed for 13-methyl-,and 13-ethylberberine(2 and 3)(1).In like fashion, in palmatine analogs tested for the first time ,activity against S.aureus increased as the length of alkyl chain rose in the order methyl, ethyl, propyl, butyl, and hexyl groups.13-Alkyl derivatives of the berberine-type, with methoxy groups at the same positions (palmatine-type).Activity against S,aureus ATCC 3061(S2) was generally lower than against S.aureus X(S1) isolated from hospitalized patients. Among the 13-alkyl substituted analogs, 13-hexyl derivatives (7 and 13) displayed the highest activity against all strains.13-Hexylberberine(7) showed the best activity against S1 and S2,with an impressive 64- and 128-fold increase over the parent berberine(1).Similarly,13-hexylpalmatine(13) demonstrated stronger activity against S1 and S2 than the parent compound by factors of 128 and 32,respectively. Among the 13-alkyl substituted analogs, 13-hexyl derivatives (7 and 13) displayed the highest activity against all strains.13-Hexylberberine (7) showed the best activity against S1 and S2,with an impressive 64- and 128-fold increase over the parent berberine(1). Similarly, 13-hexylpalmatine (13) demonstrated stronger activity against S1 and S2 than the parent compound by factors of 128 and 32,respectively. The activity of 13-hexylberberine against S2 was, in fact, comparable to that of kanamycin sulfate.13-Hexylberberine (7)and 13-hexylpalmatine (13) showed potent activity against S1,and proved to be 8 and 4 times, respectively ,superior to kanamycin sulfate .13-Hexylberberine(7) and 13-hexylpalmatine (13) showed potent activity against S1,and proved to be 8 and 4 times, respectively, superior to kanamycin sulfate.13-Hexylberberine(7) and 13-hexylpalmatine (13) also showed activity against Candida albicans IFO 1061 (MIC 15.6μg/ml) although kanamycin sulfate was inactive (MIC>2000Μg/ml). Only 13-hexylberberine(7) demonstrated a relatively high activity (MIC250μg/ml) against E.coli IFO 026,even though the activity was only one-eighth of that of kanamycin sulfate. The other 13-alkyl derivatives, except for 13-hexylpalmatine(13), exhibited weak activity (MIC>1000μ g/ml).13-Butylberberine (6) and 13-butylpalmatine (12) possessed significant activity against S.aureus. In conclusion, among the tested compounds,13-hexylberberine(7) and 13-hexylpalmatine (13) were found to be 8 and 4 times, respectively, more active against S.aureus (S1) than kanamycin sulfate.13-Hexylberberine (7) showed high activity against S.aureus (S2) comparable to that of kanamycin sulfate.13-Hexylberberine(7) and 13-hexylpalmatine (13) had very strong activity against S.aureus compared with the clinically used alkaloid berberine (1). The 13-hexyl derivatives of berberine and palmatine are highly selective in inhbiting the growth of Gram-positive, S.aureus, while they were less potent against the fungus Candida albicans .Their activities were also very low against Gram-negative E.coli. Further evaluations are required in