Stereocontrolled Total Synthesis of Bastimolide B Using Iterative Homologation of Boronic Esters.

Bastimolide B is a polyhydroxy macrolide isolated from marine cyanobacteria displaying antimalarial activity. It features a dense array of hydroxylated stereogenic centers with 1,5-relationships along a hydrocarbon chain. These 1,5-polyols represent a particularly challenging motif for synthesis, as the remote position of the stereocenters hampers stereocontrol. Herein, we present a strategy for 1,5-polyol stereocontrolled synthesis based on iterative boronic ester homologation with enantiopure magnesium carbenoids. By merging boronic ester homologation and transition-metal-catalyzed alkene hydroboration and diboration, the acyclic backbone of bastimolide B was rapidly assembled from readily available building blocks with full control over the remote stereocenters, enabling the total synthesis to be completed in 16 steps (LLS).

Outcomes for Hand Burns Treated With Autologous Skin Cell Suspension in 20% TBSA and Smaller Injuries.

In order to address the confounder of TBSA on burn outcomes, we sought to analyze our experience with the use of autologous skin cell suspensions (ASCS) in a cohort of subjects with hand burns whose TBSA totaled 20% or less. We hypothesized that the use of ASCS in conjunction with 2:1 meshed autograft for the treatment of hand burn injuries would provide comparable outcomes to hand burns treated with sheet or minimally meshed autograft alone. A retrospective review was conducted for all deep partial and full-thickness hand burns treated with split-thickness autograft (STAG) at our urban verified burn center between April 2018 and September 2020. The exclusion criterion was a TBSA greater than 20%. The cohorts were those subjects treated with ASCS in combination with STAG (ASCS(+)) vs those treated with STAG alone (ASCS(-)). All ASCS(+) subjects were treated with 2:1 meshed STAG and ASCS overspray while all ASCS(-) subjects had 1:1, piecrust, or unmeshed sheet graft alone. Outcomes measured included demographics, time to wound closure, proportion returning to work (RTW), and length of time to RTW. Mann-Whitney U test was used for comparisons of continuous variables and Fisher's exact test for categorical variables. Values are reported as medians and 25th and 75th interquartile ranges. Fifty-one subjects fit the study criteria (ASCS(+) n = 31, ASCS(-) n = 20). The ASCS(+) group was significantly older than the ASCS(-) cohort (44 [32-54] vs 32 years [27.5-37], P = .009) with larger %TBSA burns (15% [9.5-17] vs 2% [1-4], P < .0001) and larger size hand burns (190 [120-349.5] vs 126 cm2 [73.5-182], P = .015). Comparable results were seen between ASCS(+) and ASCS(-), respectively, for time to wound closure (9 [7-13] vs 11.5 days [6.75-14], P = .63), proportion RTW (61% vs 70%, P = .56), and days for RTW among those returning (35 [28.5-57] vs 33 [20.25-59], P = .52). The ASCS(+) group had two graft infections with no reoperations, while ASCS(-) had one infection with one reoperation. No subjects in either group had a dermal substitute placed. Despite being significantly older, having larger hand wounds, and larger overall wounds within the parameters of the study criteria, patients with 20% TBSA burns or smaller whose hand burns were treated with 2:1 mesh and ASCS overspray had comparable time to wound closure, proportion of RTW, and time to return to work as subjects treated with 1:1 or piecrust meshed STAG. Our group plans to follow this work with scar assessments for a more granular picture of pliability and reconstructive needs.