The melanin formation is one of the most important factors to determine the mammalian skin colour.
Tyrosinase is a mixed function oxidase enzyme which catalyzes two different reactions in the synthesis of
melanin: the formation of 3, 4-dihydroxyphenylalanine (L-DOPA) from tyrosine and further oxidizes LDOPA
to dopaquinone. Tyrosinase inhibitors may be of important to treat abnormal pigmentation disorders
and to use as skin whitening agents in cosmetics.(1) Our research group began the chemical and
pharmacological study of Dalea boliviana. We previously report the isolation and structural characterization
of three new prenylated flavanones from the hexanes extract of D. boliviana roots: (2S) - 5, 7, 2 ´ - trihydroxy-
5 ´-(1´´´,1´´´-dimethylallyl)-8-prenylflavanone (1), (2S) - 5, 7, 2´ - trihydroxy-8, 3 ´ - diprenylflavanone (2), and
(2S) - 5, 2 ´ - dihydroxy-6 ", 6"- dimethylchromeno-(7,8:2´´,3´´) - 3 ´ - prenylflavanone (3), together with a
known chromeno (dimethylpyrano) flavanone, obovatin (4).(2,3,4) Taking into account that similar compounds
have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. known chromeno (dimethylpyrano) flavanone, obovatin (4).(2,3,4) Taking into account that similar compounds
have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. (2S) - 5, 2 ´ - dihydroxy-6 ", 6"- dimethylchromeno-(7,8:2´´,3´´) - 3 ´ - prenylflavanone (3), together with a
known chromeno (dimethylpyrano) flavanone, obovatin (4).(2,3,4) Taking into account that similar compounds
have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. known chromeno (dimethylpyrano) flavanone, obovatin (4).(2,3,4) Taking into account that similar compounds
have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. 5 ´-(1´´´,1´´´-dimethylallyl)-8-prenylflavanone (1), (2S) - 5, 7, 2´ - trihydroxy-8, 3 ´ - diprenylflavanone (2), and
(2S) - 5, 2 ´ - dihydroxy-6 ", 6"- dimethylchromeno-(7,8:2´´,3´´) - 3 ´ - prenylflavanone (3), together with a
known chromeno (dimethylpyrano) flavanone, obovatin (4).(2,3,4) Taking into account that similar compounds
have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. known chromeno (dimethylpyrano) flavanone, obovatin (4).(2,3,4) Taking into account that similar compounds
have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. (2S) - 5, 2 ´ - dihydroxy-6 ", 6"- dimethylchromeno-(7,8:2´´,3´´) - 3 ´ - prenylflavanone (3), together with a
known chromeno (dimethylpyrano) flavanone, obovatin (4).(2,3,4) Taking into account that similar compounds
have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. known chromeno (dimethylpyrano) flavanone, obovatin (4).(2,3,4) Taking into account that similar compounds
have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. of three new prenylated flavanones from the hexanes extract of D. boliviana roots: (2S) - 5, 7, 2 ´ - trihydroxy-
5 ´-(1´´´,1´´´-dimethylallyl)-8-prenylflavanone (1), (2S) - 5, 7, 2´ - trihydroxy-8, 3 ´ - diprenylflavanone (2), and
(2S) - 5, 2 ´ - dihydroxy-6 ", 6"- dimethylchromeno-(7,8:2´´,3´´) - 3 ´ - prenylflavanone (3), together with a
known chromeno (dimethylpyrano) flavanone, obovatin (4).(2,3,4) Taking into account that similar compounds
have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. known chromeno (dimethylpyrano) flavanone, obovatin (4).(2,3,4) Taking into account that similar compounds
have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. (2S) - 5, 2 ´ - dihydroxy-6 ", 6"- dimethylchromeno-(7,8:2´´,3´´) - 3 ´ - prenylflavanone (3), together with a
known chromeno (dimethylpyrano) flavanone, obovatin (4).(2,3,4) Taking into account that similar compounds
have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. known chromeno (dimethylpyrano) flavanone, obovatin (4).(2,3,4) Taking into account that similar compounds
have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. 5 ´-(1´´´,1´´´-dimethylallyl)-8-prenylflavanone (1), (2S) - 5, 7, 2´ - trihydroxy-8, 3 ´ - diprenylflavanone (2), and
(2S) - 5, 2 ´ - dihydroxy-6 ", 6"- dimethylchromeno-(7,8:2´´,3´´) - 3 ´ - prenylflavanone (3), together with a
known chromeno (dimethylpyrano) flavanone, obovatin (4).(2,3,4) Taking into account that similar compounds
have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. known chromeno (dimethylpyrano) flavanone, obovatin (4).(2,3,4) Taking into account that similar compounds
have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. (2S) - 5, 2 ´ - dihydroxy-6 ", 6"- dimethylchromeno-(7,8:2´´,3´´) - 3 ´ - prenylflavanone (3), together with a
known chromeno (dimethylpyrano) flavanone, obovatin (4).(2,3,4) Taking into account that similar compounds
have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. known chromeno (dimethylpyrano) flavanone, obovatin (4).(2,3,4) Taking into account that similar compounds
have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors.
pharmacological study of Dalea boliviana. We previously report the isolation and structural characterization
of three new prenylated flavanones from the hexanes extract of D. boliviana roots: (2S) - 5, 7, 2 ´ - trihydroxy-
5 ´-(1´´´,1´´´-dimethylallyl)-8-prenylflavanone (1), (2S) - 5, 7, 2´ - trihydroxy-8, 3 ´ - diprenylflavanone (2), and
(2S) - 5, 2 ´ - dihydroxy-6 ", 6"- dimethylchromeno-(7,8:2´´,3´´) - 3 ´ - prenylflavanone (3), together with a
known chromeno (dimethylpyrano) flavanone, obovatin (4).(2,3,4) Taking into account that similar compounds
have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. known chromeno (dimethylpyrano) flavanone, obovatin (4).(2,3,4) Taking into account that similar compounds
have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. (2S) - 5, 2 ´ - dihydroxy-6 ", 6"- dimethylchromeno-(7,8:2´´,3´´) - 3 ´ - prenylflavanone (3), together with a
known chromeno (dimethylpyrano) flavanone, obovatin (4).(2,3,4) Taking into account that similar compounds
have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. known chromeno (dimethylpyrano) flavanone, obovatin (4).(2,3,4) Taking into account that similar compounds
have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. 5 ´-(1´´´,1´´´-dimethylallyl)-8-prenylflavanone (1), (2S) - 5, 7, 2´ - trihydroxy-8, 3 ´ - diprenylflavanone (2), and
(2S) - 5, 2 ´ - dihydroxy-6 ", 6"- dimethylchromeno-(7,8:2´´,3´´) - 3 ´ - prenylflavanone (3), together with a
known chromeno (dimethylpyrano) flavanone, obovatin (4).(2,3,4) Taking into account that similar compounds
have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. known chromeno (dimethylpyrano) flavanone, obovatin (4).(2,3,4) Taking into account that similar compounds
have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. (2S) - 5, 2 ´ - dihydroxy-6 ", 6"- dimethylchromeno-(7,8:2´´,3´´) - 3 ´ - prenylflavanone (3), together with a
known chromeno (dimethylpyrano) flavanone, obovatin (4).(2,3,4) Taking into account that similar compounds
have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. known chromeno (dimethylpyrano) flavanone, obovatin (4).(2,3,4) Taking into account that similar compounds
have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors.
of three new prenylated flavanones from the hexanes extract of D. boliviana roots: (2S) - 5, 7, 2 ´ - trihydroxy-
5 ´-(1´´´,1´´´-dimethylallyl)-8-prenylflavanone (1), (2S) - 5, 7, 2´ - trihydroxy-8, 3 ´ - diprenylflavanone (2), and
(2S) - 5, 2 ´ - dihydroxy-6 ", 6"- dimethylchromeno-(7,8:2´´,3´´) - 3 ´ - prenylflavanone (3), together with a
known chromeno (dimethylpyrano) flavanone, obovatin (4).(2,3,4) Taking into account that similar compounds
have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. known chromeno (dimethylpyrano) flavanone, obovatin (4).(2,3,4) Taking into account that similar compounds
have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. (2S) - 5, 2 ´ - dihydroxy-6 ", 6"- dimethylchromeno-(7,8:2´´,3´´) - 3 ´ - prenylflavanone (3), together with a
known chromeno (dimethylpyrano) flavanone, obovatin (4).(2,3,4) Taking into account that similar compounds
have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. known chromeno (dimethylpyrano) flavanone, obovatin (4).(2,3,4) Taking into account that similar compounds
have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors. have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds 1-4 as
tyrosinase inhibitors. tyrosinase inhibitors.
5 ´-(1´´´,1´´´-dimethylallyl)-8-prenylflavanone (1), (2S) - 5, 7, 2´ - trihydroxy-8, 3 ´ - diprenylflavanone (2), and
(2S) - 5, 2 ´ - dihydroxy-6 ", 6"- dimethylchromeno-(7,8:2´´,3´´) - 3 ´ - prenylflavanone (3), together with a
known chromeno (dimethylpyrano) flavanone, obovatin (4).(2,3,4) Taking into account that similar compounds
have been related to inhibition of tyrosinase activity, (5,6,7) we propose to evaluate compounds
