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1 Supporting Information Adaptation in Constitutional Dynamic Libraries and Networks, Switching between Orthogonal Metalloselection and Photoselection Processes Ghislaine Vantomme, Shimei Jiang, Jean-Marie Lehn* Standard procedure for the preparation of substituted hydrazones and acylhydrazones: Aryl aldehyde (or ketone) (1 eq.) was added to an ethanol solution of aryl hydrazine (1 eq.), or hydrazide (1 eq.) respectively. After the reaction mixture was heated under reflux for 6 hours. The precipitates were collected on a Büchner funnel. The hydrazones and acylhydrazones were obtained in a quantitative yield and were purified by recrystallization from ethanol and washed with diethyl ether. In all cases the isomer obtained was E. A lot of these hydrazones and acylhydrazones were obtained before; the spectroscopy and physical properties obtained were consistent with the literature values. [1-9] The new compounds are described below. 3 A 3 B: yellow liquid, 1 H NMR (400 MHz, CD 3 CN): δ = 8.60 (d, J = 5.0 Hz, 1H), 8.19 (d, J = 8.0 Hz, 1H), 7.79 (t, J = 8.0 Hz, 1H), 7.36 (dd, J = 8.0 Hz, J = 5.0 Hz, 1H), 7.28 (dd, J = 8.6 Hz, J = 7.3 Hz, 2H), 7.05 (d, J = 8.6 Hz, 2H), 6.91 (t, J = 7.3 Hz, 1H), 3.21 (s, 3H), 2.42 (s, 3H) ppm; 13 C NMR (400 MHz, CD 3 CN): δ = , , , , , , , , , , 43.12, 16.12; elemental analysis calculated (%) for C 14 H 15 N 3 : C 74.64, H 6.71, N 18.65; found: C 74.63, H 6.75, N ESI-MS: calculated for [C 14 H 15 N 3 +H] found A 3 B: yellow liquid, 1 H NMR (400 MHz, CD 3 CN): δ = 7.93 (m, 2H), 7.45 (m, 3H), 7.27 (d, J = 7.2 Hz, 2H), 6.98 (m, 2H), 6.88 (t, J = 7.2 Hz, 1H), 3.12 (s, 3H), 2.36 (s, 3H) ppm; 13 C NMR (400 MHz, CD 3 CN): δ = , , , , , , , , , , , 42.68, ppm; elemental analysis calculated (%) for C 15 H 16 N 2 : C 80.32, H 7.19, N 12.49; found: C 80.37, H 7.26, N ESI-MS: calculated for [C 15 H 16 N 2 +H] found A 2 B: yellow liquid, 1 H NMR (400 MHz, CD 3 CN): δ = 8.62 (d, J = 5.0 Hz, 1H), 8.23 (d, J = 5.0 Hz, 1H), 8.20 (d, J = 7.8 Hz, 1H), 7.80 (t, J = 7.8 Hz, 1H), 7.57 (t, J = 8.0 Hz, 1H), 7.38 (dd, J = 7.8 Hz, J = 5.0 Hz, 1H), 7.01 (d, J = 8.0 Hz, 1H), 6.80 (dd, J = 8.0 Hz, J = 5.0 Hz, 1H), 3.40 (s, 3H), 2.49 (s, 3H) ppm; 13 C NMR (400 MHz, CD 3 CN): δ = , , , , , , , , , ppm; elemental analysis calculated (%) for C 13 H 14 N 4 : C 69.00, H 6.24, N 24.76; found: C 68.74, H 6.16, N ESI-MS: calculated for [C 13 H 14 N 4 +H] found A 2 B: yellow liquid, 1 H NMR (400 MHz, CD 3 CN): δ = 8.22 (d, J = 5.0 Hz, 1H), 7.95 (m, 2H), 7.55 (dd, J = 8.7 Hz, J = 7.0 Hz, 1H), 7.46 (m, 3H), 6.86 (d, J = 8.7 Hz, 1H), 6.77 (dd, J = 7.8 Hz, J = 5.0 Hz, 1H), 3.29 (s, 3H), 2.40 (s, 3H); 13 C NMR (400 MHz, CD 3 CN): δ = , , , , , , , , , , 39.17, ppm; elemental analysis calculated (%) for C 14 H 15 N 3 : C 74.64, H 6.71, N 18.65; found: C 74.08, H 6.61, N ESI-MS: calculated for [C 14 H 15 N 3 +H] found A 3 B: red solid, 1 H NMR (400 MHz, CD 3 Cl 3 ): δ = 8.25 (d, J = 9.0 Hz, 2H), 8.11 (d, J = 9.0 Hz, 2H), 7.30 (dd, J = 8.7 Hz, J = 7.3 Hz, 1H), 7.06 (d, J = 8.7 Hz, 1H), 6.93 (t, J = 7.3 Hz, 1H), 3.21 (s, 3H), 2.38 (s, 3H); 13 C NMR (400 MHz, CD 3 CN): δ = , , , , , , , , , 43.46, ppm; elemental analysis calculated (%) for C 15 H 15 N 3 O 2 : C 66.90, H 5.61, N 15.60; found: C 66.96, H 5.70, N ESI-MS: calculated for [C 15 H 15 N 3 O 2 +H] found S1

2 Crystals of 5 A 3 B visible on figure 2 were obtained by slow evaporation of a solution in an ethyl acetate/heptane 1/9. 5 A 2 B: orange solid, 1 H NMR (400 MHz, CD 3 Cl 3 ): δ = 8.25 (m, 3H), 8.13 (d, J = 9.1 Hz, 2H), 7.60 (dd, J = 8.5 Hz, J = 7.8 Hz, 1H), 7.02 (d, J = 8.5 Hz, 1H), 6.83 (dd, J = 7.8 Hz, J = 5.0 Hz, 1H), 3.26 (s, 3H), 2.44 (s, 3H); 13 C NMR (400 MHz, CD 3 CN): δ = , , , , , , , , , , 39.65, ppm; elemental analysis calculated (%) for C 15 H 15 N 3 O 2 : C 62.21, H 5.22, N 20.73; found: C 62.20, H 5.24, N ESI-MS: calculated for [C 14 H 14 N 4 O 2 +H] found A 2 C: slightly yellow solid, 1 H NMR (400 MHz, CD 3 CN): δ = 8.61 (d, J = 4.3 Hz, 1H), 7.75 (m, 2H), 7.53 (m, 2H), 7.40 (m, 4H), 3.35 (s, 3H), 2.40 (s, 3H) ppm; 13 C NMR (400 MHz, CD 3 CN): δ = , , , , , , , ppm; elemental analysis calculated (%) for C 15 H 15 N 3 O 1 : C 71.13, H 5.97, N 16.59; found: C 71.16, H 5.92, N ESI-MS: calculated for [C 14 H 13 N 3 O 1 +H] found A 3 C: yellow liquid, 1 H NMR (400 MHz, CD 3 CN): δ = 8.61 (d, J = 4.8 Hz, 1H), 7.95 (d, J = 7.7 Hz, 1H), 7.77 (t, J = 7.7 Hz, 1H), 7.46 (d, J = 9.2 Hz, 2H), 7.40 (dd, J = 7.7 Hz, J = 4.8 Hz, 1H), 6.65 (d, J = 9.2 Hz, 2H), 3.34 (s, 3H), 2.96 (s, 6H), 2.38 (s, 3H) ppm; 13 C NMR (400 MHz, CD 3 CN): δ = , , , , , , , , , 40.30, ppm. ESI-MS: calculated for [C 17 H 20 N 4 O 1 +H] found A 3 C: slightly yellow solid, 1 H NMR (400 MHz, CD 3 CN): δ = 7.86 (s, 1H), 7.73 (d, J = 9.0 Hz, 2H), 7.58 (m, 2H), 7.36 (m, 3H), 6.90 (d, J = 9.0 Hz, 2H), 3.47 (s, 3H), 3.02 (s, 6H) ppm; 13 C NMR (400 MHz, CD 3 CN): δ = , , , , , , , , , , , , 41.34, ppm. ESI-MS: calculated for [C 17 H 19 N 3 O 1 +H] found A 3 C: slightly yellow solid, 1 H NMR (400 MHz, CD 3 CN): δ = 8.56 (d, J = 4.7 Hz, 1H), 7.85 (s, 1H), 7.71 (m, 4H), 7.28 (dd, J = 7.2 Hz, J = 4.7 Hz, 1H), 6.75 (d, J = 9.0 Hz, 2H), 3.50 (s, 3H), 3.03 (s, 6H) ppm; 13 C NMR (400 MHz, CD 3 CN): δ = , , , , , , , , , , , 40.35, ppm. ESI-MS: calculated for [C 16 H 18 N 4 O 1 +H] found The solid state molecular structure of the acylhydrazone 1 A 3 C (below). Crystals of 1 A 3 C were obtained by slow evaporation of an ethanol solution. 1 A 2 C: white solid, 1 H NMR (400 MHz, CD 3 CN): δ = 8.55 (d, J = 4.8 Hz, 1H), 7.88 (s, 1H), 7.66 (m, 3H), 7.48 (m, 4H), 7.26 (dd, J = 7.6 Hz, J = 4.8 Hz, 1H), 3.53 (s, 3H) ppm; 13 C NMR (400 MHz, CD 3 CN): δ = , , , , , , , , , , , ppm; elemental analysis calculated (%) for C 14 H 13 N 3 O 1 : C 70.28, H 5.48, N 17.56; found: C 70.39, H 5.50, N ESI-MS: calculated for [C 14 H 13 N 3 O 1 +H] found S2

3 S1. Adaptation in a CDL of hydrazones 1.1 Component exchange in the two DCLs of hydrazones [ 1 A 1 B, 1 A 2 B, 2 A 1 B, 2 A 2 B] and [ 3 A 2 B, 3 A 3 B, 4 A 2 B, 4 A 3 B]. i) Metal ion catalysis. One may note that a yellow coloration of the solution was obtained when some of the hydrazones were mixed with scandium triflate. Figure S1. A portion of the 400 MHz 1 H NMR spectrum of the two hydrazones 1 A 1 B and 2 A 2 B (10 mm in CD 3 CN/D 2 O 4/1) with 2 mm Sc(OTf) 3 before (top trace) and after (bottom trace) 40 minutes at 170 C in the microwave oven showing the hydrazones exchange. S3

4 Figure S2. A portion of the 400 MHz 1 H NMR spectrum of the hydrazone E- 1 A 1 B (10 mm in CD 3 CN/D 2 O 4/1) after 40 minutes at 170 C into the microwave oven showing isomerization from the E isomer to the Z (63% and 37% respectively). Figure S3. A portion of the 400 MHz 1 H NMR spectrum of the hydrazone Z- 1 A 1 B (10 mm in CD 3 CN/D 2 O 4/1) after 40 minutes at 170 C into the microwave oven showing isomerization from the E isomer to the Z (63% and 37% respectively). S4

5 ii) Organo-catalysis. Figure S4. A portion of the 400 MHz 1 H NMR spectrum of the two hydrazones 1 A 1 B and 2 A 2 B (10 mm in CD 3 CN) with 10% of aniline in volume before (top trace) and after (bottom trace) one day at 25 C showing the hydrazones exchange, with also almost 50% of isomerization of E- 1 A 1 B into Z- 1 A 1 B. Signals at 6.7 and 7.1 ppm are protons of aniline. Other organo-catalysts have also been tested. The same exchange equilibrium was obtained using aniline, 4-bromoaniline, 4-fluoroaniline, 5-methoxyanthranilic acid or 3,5-diaminobenzoic acid as catalysts. No exchange were observed with N,N-dimethylaniline, piperidine, 4-aminopyridine or butylamine. S5

6 iii) Strain activation in the DCL of hydrazones 3 A 2 B, 3 A 3 B, 4 A 2 B and 4 A 3 B. Figure S5. A portion of the 400 MHz 1 H NMR spectrum of the two hydrazones 3 A 3 B and 4 A 2 B (10 mm in CD 3 CN) with 2 mm Sc(OTf) 3 before (top trace) and after (bottom trace) 12 hours at 60 C showing the hydrazones exchange favored by the steric strain caused by CH 3 /CH 3 interaction on these compounds. Figure S6. The solid state molecular structures of the hydrazones 3 A 2 B complexed with the zinc (II) cations chlorides. The carbon C6 and the nitrogen N3 are disordered. The complexes are bridged through ZnCl 4 2- anions. (left) front view and (right) side view of the complex. Crystals of ( 3 A 2 B,Zn)Cl 2 were obtained by vapor diffusion of diisopropylether into a solution of 3 A 2 B and ZnCl 2 in acetonitrile/chloroform 1/1. S6

7 1.2 Metalloselection in the three DCLs of hydrazones: [ 1 A 1 B, 1 A 2 B, 2 A 1 B, 2 A 2 B], [ 3 A 2 B, 3 A 3 B, 4 A 2 B, 4 A 3 B] and [ 3 A 2 B, 3 A 3 B, 5 A 2 B, 5 A 3 B] Pyridyl-hydrazones are known to form stable complexes with a variety of metal cations by coordination to the NNN tridentate site, as in the case below: Figure S7. The solid state molecular structure of the hydrazones E- 1 A 4 B complexed with the zinc (II) chlorides. A hydrogen bond is formed between the N-H group of E- 1 A 4 B,Zn and a chloride ion coordinated to another complex. Crystals of (E- 1 A 4 B,Zn)Cl 2 were obtained by vapor diffusion of diisopropylether into a solution of E- 1 A 4 B and ZnCl 2 in acetonitrile/chloroform 1/1. Figure S8. A portion of the 400 MHz 1 H NMR spectrum of the library of hydrazones 1 A 1 B, 1 A 2 B, 2 A 1 B and 2 A 2 B formed by exchange between 1 A 1 B and 2 A 2 B (10 mm in CD 3 CN/D 2 O 4/1) before (top trace) and after (bottom trace) addition of 5 mm Zn(OTf) 2 and heating during 20 minutes at 170 C in the microwave oven showing metalloselection by amplification of the hydrazone 1 A 2 B in the form of its Zn( 1 A 2 B) 2 complex as well as simultaneously its agonist 2 A 1 B. S7

8 Figure S9. A portion of the 400 MHz 1 H NMR spectrum of the two hydrazones 1 A 1 B and 2 A 2 B (10 mm in CD 3 CN) with 10% aniline in volume before (top trace) and after (bottom trace) addition of 5 mm Zn(OTf) 2 and heating during 6 hours at 80 C showing metalloselection by amplification of the hydrazone 1 A 2 B in the form of its Zn( 1 A 2 B) 2 complex as well as simultaneously its agonist 2 A 1 B. Signals at 6.7 and 7.1 ppm are protons of aniline. Figure S10. A portion of the 400 MHz 1 H NMR spectrum of the library of hydrazones 3 A 2 B, 3 A 3 B, 4 A 2 B and 4 A 3 B with 5 mm Zn(OTf) 2 formed by exchange between 3 A 3 B and 4 A 2 B (10 mm in CD 3 CN) before (top trace) and after (bottom trace) overnight at 60 C showing metalloselection by amplification of the hydrazone 3 A 2 B in the form of its Zn( 3 A 2 B) 2 complex as well as simultaneously its agonist 4 A 3 B. S8

9 1.3 Attempts of photoselection in the DCL of hydrazones [ 1 A 1 B, 1 A 2 B, 2 A 1 B, 2 A 2 B] Irradiation procedure: The sample contained in an NMR tube was placed in a water bath in a thermostated beaker at 25 C in front of a xenon short arc lamp (a Müller Elektronik Optik Light Source Model LAX 1000 / SVX 1000 with a xenon short arc lamp XBO 1000 W / HS OFR from Osram). Irradiation was performed with a cut-off at 275 nm, so as to eliminate the short wavelength UVC light. Figure S11. Picture of the test of the light irradiation directly inside the microwave oven. The lamp (on the left) irradiates the solution inside the microwave (on the right) by a hole usually made to add an optional camera. Figure S12. The solid state molecular structure of the hydrazones Z- 1 A 4 B complexed with the zinc (II) chlorides, showing clearly the intramolecular hydrogen bond formed in Z- 1 A 4 B. Crystals of (Z- 1 A 4 B,Zn)Cl 2 were obtained by vapor diffusion of diisopropylether into a solution of Z- 1 A 4 B and ZnCl 2 in acetonitrile/chloroform 1/1. Zinc salts were added here to improve the crystallization of Z- 1 A 4 B. S9

10 S2. Adaptation in a CDL of acylhydrazones 2.1 Component exchange in the three DCLs of acylhydrazones [ 1 A 1 C, 1 A 2 C, 2 A 1 C, 2 A 2 C], [ 1 A 1 C, 1 A 3 C, 2 A 1 C, 2 A 3 C] and [ 3 A 3 C, 3 A 2 C, 4 A 3 C, 4 A 2 C] Figure S13. A portion of the 400 MHz 1 H NMR spectrum of the two acylhydrazones 1 A 2 C and 2 A 1 C (10 mm in CD 3 CN/D 2 O 3/2) with 0.2 mm Sc(OTf) 3 before (top trace) and after (bottom trace) 12 hours at 60 C showing the acylhydrazones exchange with also almost 25% of isomerization of E- 1 A 1 C into Z- 1 A 1 C. Figure S14. A portion of the 400 MHz 1 H NMR spectrum of the two acylhydrazones 1 A 1 C and 2 A 2 C (10 mm in CD 3 CN) with 1% of aniline in volume after two hours at 25 C showing the acylhydrazones S10

11 exchange, with also almost 52% of isomerization of E- 1 A 1 C into Z- 1 A 1 C. Signals at 6.6 and 7.1 ppm are protons of aniline. Figure S15. A portion of the 400 MHz 1 H NMR spectrum of the two acylhydrazones 1 A 3 C and 2 A 1 C (10 mm in CD 3 CN/D 2 O 3/2) with 0.2 mm Sc(OTf) 3 before (top trace) and after (bottom trace) 12 hours at 60 C showing the acylhydrazones exchange. Figure S16. A portion of the 400 MHz 1 H NMR spectrum of the two acylhydrazones 1 A 1 C and 2 A 3 C (10 mm in CD 3 CN) with 1% of aniline in volume after two hours at 25 C showing the acylhydrazones exchange. Signals at 6.6 and 7.1 ppm are protons of aniline. S11

12 Figure S17. A portion of the 400 MHz 1 H NMR spectrum of the two acylhydrazones 3 A 3 C and 4 A 2 C (10 mm in CD 3 CN) with 2 mm Sc(OTf) 3 after twelve hours at 25 C showing the acylhydrazones exchange with 50% hydrolysis. Figure S18. The solid state molecular structures of the dimeric complex formed from two ( 3 A 2 C,Pb)OTf 2 1:1 complexes by bridging through two triflate counterions. The pyridine-c(ch 3 )=N - moiety lies in the plane of the figure while the =N -N (CH 3 )-C(=O)-phenyl moiety is located in a plane making a dihedral angle of about 65. Crystals of ( 3 A 2 C,Pb)OTf 2 were obtained by vapor diffusion of diisopropylether into a solution of 3 A 2 C and PbOTf 2 in acetonitrile/chloroform 1/1. S12

13 2.2 Photoselection in the DCL of the acylhydrazones [E- 1 A 1 C, 1 A 2 C, 2 A 1 C, 2 A 2 C] Figure S19. A portion of the 400 MHz 1 H NMR spectrum of the two acylhydrazones 1 A 2 C and 2 A 1 C (10 mm in CD 3 CN/D 2 O 3/2) with 2 mm Sc(OTf) 3 before (top trace) and after (bottom trace) four hours at 25 C in front of the light showing photoselection by amplification of the hydrazone 1 A 1 C in its Z form as well as simultaneously its agonist 2 A 2 C. 2.3 Metalloselection and photoselection in the DCL of acylhydrazones [E- 1 A 1 C, 1 A 3 C, 2 A 1 C, 2 A 3 C] Pyridyl-acylhydrazones bind metal cations by their tridentate NNO coordination site. Here are some solid-state molecular structures of acylhydrazones complexes. Figure S20. The solid state molecular structures of the dimeric complex form from two acylhydrazones 1 A 1 C complexed with silver (I) perchlorate. The silver cation is tetracoordinated. The two N-H groups of the complex ( 1 A 1 C) 2,Ag participate to two different intermolecular hydrogen bonds: on one side with a perchlorate anion, and on the other side with the oxygen of another complex. Crystals of [( 1 A 1 C) 2,Ag]ClO 4 were obtained by vapor diffusion of diisopropylether into a solution of 1 A 1 C and AgClO 4 in acetonitrile/chloroform 1/1. S13

14 Figure S21. The solid state molecular structures of the dimeric complex formed from two acylhydrazones 1 A 1 C complexed with barium (II) perchlorate. Intermolecular hydrogen bonds are formed between the N-H group and the perchlorate anions. Crystals of [( 1 A 1 C) 2,Ba](ClO 4 ) 2 were obtained by vapor diffusion of diisopropylether into a solution of 1 A 1 C and Ba(ClO 4 ) 2 in acetonitrile/chloroform 1/1. Figure S22. The solid state molecular structures of the acylhydrazones 1 A 1 C complexed with zinc (II) chloride. Intermolecular hydrogen bond is formed between the N-H group and the chloride anion. Crystals of ( 1 A 1 C,Zn)Cl 2 were obtained by vapor diffusion of diisopropylether into a solution of 1 A 1 C and ZnCl 2 in acetonitrile/chloroform 1/1. Figure S23. A portion of the 400 MHz 1 H NMR spectrum of the library of acylhydrazones 1 A 1 C, 1 A 3 C, 2 A 1 C and 2 A 3 C with 5 mm Zn(OTf) 2 formed by exchange between 1 A 1 C and 2 A 3 C (10 mm in CD 3 CN/D 2 O 3/2) before (top trace) and after (bottom trace) overnight at 25 C showing S14

15 metalloselection by amplification of the hydrazone 1 A 3 C in the form of its Zn( 1 A 3 C) 2 complex as well as simultaneously its agonist 2 A 1 C. Figure S24. A portion of the 400 MHz 1 H NMR spectrum of the four acylhydrazones 1 A 1 C, 2 A 1 C, 1 A 3 C and 2 A 3 C (5 mm in CD 3 CN) with 1% aniline in volume and 5 mm Zn(OTf) 2 before (top trace) and after (bottom trace) 30 minutes at 25 C showing metalloselection by amplification of the hydrazone 1 A 3 C in the form of its Zn( 1 A 3 C) 2 complex as well as simultaneously its agonist 2 A 1 C. Signals at 6.6 and 7.1 ppm are protons of aniline. Figure S25. A portion of the 400 MHz 1 H NMR spectrum of the two acylhydrazones 1 A 3 C and 2 A 1 C (10 mm in CD 3 CN/D 2 O 3/2) with 2 mm Sc(OTf) 3 before (top trace) and after (bottom trace) four hours at S15

16 25 C in front of the light showing photoselection by amplification of the hydrazone 1 A 1 C in its Z form as well as simultaneously its agonist 2 A 3 C. References [1] For the compounds 1 A 1 B, 2 A 3 B and 1 A 1 C, see for instance: Chaur, M. N.; Collado, D.; Lehn, J.-M. Chem. Eur. J. 2011, 17, [2] For the compound 1 A 2 B, see for instance: Abu-El-halawah, R.; Fares Ali, B.; Fares Kayed, S.; Baker, H.; Qandil, M.; Al-Refai, M.; Ibrahim, M.; Juddeh, Z.; Hashim Al-Obaidi, K. J. Coord. Chem. 2004, 57, [3] For the compound 2 A 1 B, see for instance: Vickery, B.; Willey, G. R.; Drew, M. G. B. Acta Crystallogr., Sect. C: Cryst. Struct. Commun. 1985, C41, [4] For the compound 2 A 2 B, see for instance: Abu-El-Halawa, R.; Al-Nuri, M.; Mahmoud, F. Asian J. Chem. 2007, 19, [5] For the compound 2 A 1 C, see for instance: Al-Farkh, Y. A.; Al-Hajjar, F. H.; Hamoud, H. S. J. Chem. Eng. Data 1978, 23, [6] For the compound 2 A 2 C, see for instance: Al-Awadi, N. A.; Ibrahim, Y. A.; Patel, M.; George, B. J.; Al-Etiabi, A. M. Int. J. of Chem. Kinet. 2007, 39, [7] For the compound 4 A 2 C, see for instance: Berger, R.; Duff, K.; Leighton, J. L. J. Am. Chem. Soc. 2004, 126, [8] For the compound 4 A 1 C, see for instance: Fun, H.-K.; Sujith, K. V.; Patil, P.S.; Kalluraya, B.; Chantrapromma, S. Acta Crystallogr., Sect. E: Struct. Rep. Online 2008, 64, [9] For the fragment 3 C, see for instance: Degorce, S.; Delouvrie, B.; Davey, P. R. J.; Didelot, M.; Germain, H.; Harris, Cr. S.; Brempt Lambert-van der, C.; Lebraud, H.; Ouvry, G. Tetrahedron Lett. 2012, 53, S16