The Spirastrellolides: Construction of the Southern C(1)−C(25) Fragment Exploiting Anion Relay Chemistry

Effective construction of the southern C(1)−C(25) fragment of spirastrellolide A has been achieved. Central to this venture was the use of four dithiane unions, including the highly effective deployment of the anion relay chemistry (ARC) tactic recently introduced by our laboratory

A General, Convergent Strategy for the Construction of Indolizidine Alkaloids: Total Syntheses of (−)-Indolizidine 223AB and Alkaloid (−)-205B^†

N-Toluenesulfonyl aziridines comprise effective second electrophiles in the solvent controlled three-component linchpin union of silyl dithianes for the stereocontrolled convergent elaboration of protected 1,5-amino alcohols. This tactic, in conjunction with a one-flask sequential cyclization, constitutes an effective general strategy for the construction of indolizidine and related alkaloids, illustrated here with the total syntheses of (−)-indolizidine 223AB (1) and alkaloid (−)-205B (2)

The Spirastrellolides: Construction of the Southern C(1)−C(25) Fragment Exploiting Anion Relay Chemistry

Effective construction of the southern C(1)−C(25) fragment of spirastrellolide A has been achieved. Central to this venture was the use of four dithiane unions, including the highly effective deployment of the anion relay chemistry (ARC) tactic recently introduced by our laboratory

A General, Convergent Strategy for the Construction of Indolizidine Alkaloids: Total Syntheses of (−)-Indolizidine 223AB and Alkaloid (−)-205B^†

N-Toluenesulfonyl aziridines comprise effective second electrophiles in the solvent controlled three-component linchpin union of silyl dithianes for the stereocontrolled convergent elaboration of protected 1,5-amino alcohols. This tactic, in conjunction with a one-flask sequential cyclization, constitutes an effective general strategy for the construction of indolizidine and related alkaloids, illustrated here with the total syntheses of (−)-indolizidine 223AB (1) and alkaloid (−)-205B (2)

A General, Convergent Strategy for the Construction of Indolizidine Alkaloids: Total Syntheses of (−)-Indolizidine 223AB and Alkaloid (−)-205B^†

N-Toluenesulfonyl aziridines comprise effective second electrophiles in the solvent controlled three-component linchpin union of silyl dithianes for the stereocontrolled convergent elaboration of protected 1,5-amino alcohols. This tactic, in conjunction with a one-flask sequential cyclization, constitutes an effective general strategy for the construction of indolizidine and related alkaloids, illustrated here with the total syntheses of (−)-indolizidine 223AB (1) and alkaloid (−)-205B (2)

Total Synthesis of the Neotropical Poison-Frog Alkaloid (−)-205B

A stereocontrolled total synthesis of the neotropical poison-frog alkaloid (−)-205B (1) has been achieved, employing a dithiane three-component linchpin coupling, a one-pot sequential construction of the embedded indolizidine ring, and ring-closing metathesis (RCM) to arrive at the novel 8b-azaacenaphthylene ring system comprising the alkaloid. The synthesis proceeded with a longest linear sequence of 19 steps, affording (−)-1 in 5.6% overall yield

Total Synthesis of the Neotropical Poison-Frog Alkaloid (−)-205B

A stereocontrolled total synthesis of the neotropical poison-frog alkaloid (−)-205B (1) has been achieved, employing a dithiane three-component linchpin coupling, a one-pot sequential construction of the embedded indolizidine ring, and ring-closing metathesis (RCM) to arrive at the novel 8b-azaacenaphthylene ring system comprising the alkaloid. The synthesis proceeded with a longest linear sequence of 19 steps, affording (−)-1 in 5.6% overall yield

The Spirastrellolides: Construction of the Southern C(1)−C(25) Fragment Exploiting Anion Relay Chemistry

Effective construction of the southern C(1)−C(25) fragment of spirastrellolide A has been achieved. Central to this venture was the use of four dithiane unions, including the highly effective deployment of the anion relay chemistry (ARC) tactic recently introduced by our laboratory

Multicomponent Linchpin Coupling of Silyl Dithianes Employing an <i>N</i>-Ts Aziridine as the Second Electrophile: Synthesis of (−)-Indolizidine 223AB

An efficient, stereocontrolled assembly of the indolizidine alkaloid, (−)-indolizidine 223AB, exploiting a three-component linchpin coupling employing an N-Ts aziridine as the second electrophile, followed by a one-pot sequential construction of the indolizidine ring system, has been achieved. The longest linear sequence was 10 steps, proceeding in 10% overall yield

A General, Convergent Strategy for the Construction of Indolizidine Alkaloids: Total Syntheses of (−)-Indolizidine 223AB and Alkaloid (−)-205B^†

N-Toluenesulfonyl aziridines comprise effective second electrophiles in the solvent controlled three-component linchpin union of silyl dithianes for the stereocontrolled convergent elaboration of protected 1,5-amino alcohols. This tactic, in conjunction with a one-flask sequential cyclization, constitutes an effective general strategy for the construction of indolizidine and related alkaloids, illustrated here with the total syntheses of (−)-indolizidine 223AB (1) and alkaloid (−)-205B (2)